Author: Eric Gomez

Taiwan Arms Sale Backlog, October 2025 Update

Delays Mount for F-16s, Torpedoes

By Eric Gomez

The backlog of US arms sales notified to Congress slightly worsened in October 2025, as senior Lai administration officials admitted to new delays while under questioning by lawmakers in the Legislative Yuan (LY). A summit between Donald Trump and Xi Jinping did not result in any significant changes to US policy toward Taiwan, which suggests that future arms sales remain on the table. A new “T-Dome” initiative for air and missile defense, announced by President Lai, offers hints as to what Taiwan wants to prioritize; however, no new arms sales were notified to Congress in October.

We assess the Taiwan arms sale backlog to be unchanged from September 2025. The topline dollar value of the backlog remains $21.54 billion, though in-progress deliveries of Abrams tanks and Harpoon Coastal Defense Systems mean the true dollar value is lower than the topline. Figure 1 illustrates the breakdown of the backlog between asymmetric weapons, traditional weapons, and munitions. Table 1 provides an itemized list of all arms sales in the backlog, including the most up-to-date information on their status.

New Information about Delayed Arms Sales

Senior Lai administration officials revealed new information about several delayed arms sales after being questioned by members of the LY this month.

As Taiwan Security Monitor has previously reported, Taiwan has yet to receive its first newly built F-16 Block 70/72 fighter aircraft, despite the first one rolling off the assembly line in March 2025. The delivery timeline for the first aircraft has been nudged back several times, but until October, press reports consistently said that deliveries were expected to begin before the end of the year. In June 2025, the Air Force Chief of Staff told the LY that he was “optimistic” that at least 10 F-16s would arrive in Taiwan by the end of 2025.

This month, Premier Cho Jung-tai informed lawmakers that 10 F-16s will be assembled by the end of the year; however, they will not begin arriving in Taiwan until sometime in 2026. Moreover, Cho did not specify when full delivery would take place. To put this new timeline in context, in June 2024 Minister of National Defense Wellington Koo testified to lawmakers that he anticipated taking delivery of the first aircraft in the fourth quarter of 2024, with full delivery of 66 aircraft occurring by the end of 2026.

The same press report on Cho’s comments to lawmakers mentioned two other delayed arms sales: the AGM-154C glide bomb and Mk-48 heavyweight torpedoes. The AGM-154C has long been one of the most egregious delayed arms sales in the backlog. Congress received notification of the sale of 50 AGM-154Cs in June 2017. However, a contract to produce the weapons was not finalized until February 2024, almost seven years later. The MND releases periodic updates to the LY on the status of arms sales, and the AGM-154C has been considered a delayed sale in those reports since at least March 2024.

Mk-48 heavyweight torpedoes, however, are a new addition to the category of delayed arms sales. MND has been very tight-lipped about the Mk-48s, which are intended to arm Taiwan’s new, indigenously produced submarine, which is also experiencing mounting delays in undergoing sea trials. The first Mk-48 sale was notified to Congress simultaneously with the AGM-154C sale, and a second notification for torpedoes was issued in May 2020. Prior to October 2025, the last update on the torpedoes came in September 2025, when press reports said that Taiwan would receive 14 torpedoes in 2027 and 10 in 2028 (this falls short of the 46 torpedoes notified to Congress).

In early November, the most recent version of the MND report to the LY on arms sale delivery status was publicly released; however, Taiwan Security Monitor has not yet finished translating it. Based on previous versions of this report, the most recent version should have more detailed delivery timelines for the three arms sales that MND considers delayed. We will post a full translation of this report once it is available and include more information about delivery delays in the November 2025 monthly update.

“T-Dome” Shines Spotlight on Air and Missile Defense

Another significant development in October 2025 was President Lai’s announcement in his National Day speech that Taiwan would begin work on a “T-Dome” system to improve its air and missile defense capabilities.

While details about “T-Dome” are still scarce, its name references Israel’s “Iron Dome” system—a layered missile defense system that utilizes a variety of sensors and interceptors to intercept threats ranging from simple, unguided rockets to medium-range ballistic missiles. The air and missile threat facing Taiwan has important differences from that facing Israel, but that is a discussion for another time. For arms sales, Taiwan will likely lean more heavily on the United States to bolster its air defense capabilities.

There are already indications that Taiwan is considering significant purchases of US air defense systems. The MND has requested funding to purchase nearly 2,000 additional Stinger missiles on top of 500 that are supposed to arrive in Taiwan by the end of this year. The 2026 defense budget submitted to the LY a few months ago included a phase two of NASAMS procurement that would add nine more batteries and over 300 missiles to the three batteries and 123 missiles notified to Congress last year. Finally, in October 2025, press reports indicated that Taiwan is considering a large purchase of four additional Patriot batteries and up to 500 interceptors.

To be clear, none of the above arms sales have been notified to Congress yet, and until they are, they should be considered hypothetical rather than real. However, it is positive that Taiwan is willing to make significant investments in asymmetric air defense capabilities. The key variable in this discussion is what happens to the special five-year procurement budget that is up for consideration in the LY. Taiwan and the United States are likely waiting for the special budget issue to work itself out before any new arms sales move further down the process of being notified to Congress, as Taiwan needs to have funding lined up for an arms sale before it can move ahead with signing a Letter of Offer and Acceptance (LOA), which details a payment and delivery schedule. Congressional notification precedes LOA signature.

Conclusion

The October 2025 data reinforces a now-familiar pattern: Taiwan’s arms sale backlog is not growing, but existing delays are becoming more severe and visible. The slippage of major programs, such as the F-16s, AGM-154C glide bombs, and now the Mk-48 torpedoes, highlights persistent bottlenecks in U.S. production capacity and the long timelines required to move weapons from notification to delivery. At the same time, emerging initiatives such as President Lai’s “T-Dome” concept signal where Taiwan intends to invest next, particularly in layered air and missile defense.

Whether these potential purchases meaningfully reshape the backlog will depend on the fate of Taiwan’s five-year special procurement budget and the ability of both Washington and Taipei to align funding, contracting, and delivery schedules. November’s release of updated MND reporting should clarify how far timelines have slipped, and whether progress toward new air defense systems offsets mounting delays in legacy programs.

Taiwan Arms Backlog Data_October 2025 Download

Taiwan Arms Sale Backlog, September 2025 Update

Partial Deliveries, Future Schedules and Co-Production News

By Eric Gomez and Joseph O’Connor

There were many updates to US arms sale cases to Taiwan, but no new Foreign Military Sales (FMS) cases were announced, and no deliveries were completed, so our dataset has not changed from last month. We assess the current backlog to be $21.54 billion.

See Figure 1 for a breakdown of this total by category and Table 1 for an itemized list of the FMS cases in the backlog with the latest available information on their status.

Before getting into updates from September 2025, we wanted to explain why our dataset has remained fixed at $21.54 billion despite more information coming out about partial deliveries.

A Note on Methodology
Our dataset retains the full dollar value of an arms sale case as notified to Congress until the arms package is fully delivered. However, as 2025 has progressed, many packages have been partially delivered. This means that the dataset’s top-line backlog dollar value of $21.54 billion is inaccurate.
While we are aware of this accuracy issue, we are not changing the dataset’s methodology at this time and wanted to explain why.

First, FMS cases typically include many more pieces of equipment than the headline item. The sale of 108 Abrams tanks, for example, includes tank recovery vehicles, munitions, machine guns, and spare parts. Reducing the backlog’s dollar value by a fraction of the number of tanks delivered would therefore also produce an inaccurate number.

Second, while it may be easy to track partial deliveries of weapons systems with a bigger media following, like tanks and aircraft, most of the backlog consists of platforms that are smaller in both size and level of attention, making it harder to determine when partial delivery has occurred.

Third, it is not always possible to determine the scale of a partial delivery. For larger capabilities like HIMARS, F-16s, and Abrams tanks, it is easy to keep track of what is in Taiwan and what is not, but for many other cases, precise numbers are not available. The partial delivery of Altius drones from August 2025 is an instructive recent example of this. As of the end of September, no specific number of drones has been mentioned as being delivered, only a “first batch.”

While our current methodology is imperfect, due to data availability constraints, we are concerned that attempting to adjust the backlog’s dollar value based on partial deliveries would also produce an inaccurate number. Therefore, we will stick with our existing methodology despite its flaws.

Additionally, we have made two changes to the Excel file that accompanies these blog posts. First, we deleted the sheet that tracked US arms transfers to Ukraine and their overlap with arms sales to Taiwan because of changes in the overall level of US military aid to Ukraine and a general lack of new information from the State Department. Second, the sheet tracking all FMS cases since the beginning of the Ukraine war had become very long, so we disaggregated it. The new sheets are now labeled “Global FMS Cases 2022,” “Global FMS Cases 2023,” etc.

New Information on Partial Delivery of Switchblade Drones
A press report from Taiwan’s Liberty Times, citing the Ministry of National Defense (MND) 2026 budget request, indicates that, in addition to the partial delivery of Altius-600M drones last month, Taiwan has also started receiving Switchblade 300 drones. The Military Police Command has already received 66 Switchblade drones. The army is receiving 619 Switchblades, with 150 expected by the end of 2025 and 469 by the end of 2026. The original Congressional notification for the Switchblade sale had 720 drones, but from the press report and other sources, this number has evidently been reduced to 685.

The same press report also indicated that a second batch of Altius-600M drones should arrive in Taiwan by the end of 2025, which would complete the FMS case. If the defense industry can stick to these delivery schedules, it will be a significant achievement in the speedy delivery of FMS cases. Both cases were notified to Congress in mid-June 2024, meaning that it took just slightly over a year to go from notification to initial delivery. In the world of arms sales, this is a breakneck pace. Given Taiwan’s urgent need for large numbers of unmanned systems to offset China’s military advantages, the rapid pace of Switchblade and Altius deliveries is a heartening development.

Updated Delivery Timelines for Multiple Arms Sales
We were able to find new information about delivery timelines for five arms sale cases in the backlog. These are covered in alphabetical order.

AN/TPS-77/78 Radar Systems
In October 2024, Congress was notified of an FMS case for an unspecified number of AN/TPS-77 and AN/TPS-78 mobile air defense radar systems valued at $828 million. A press report in September 2025 provided more information about the number of radar systems being procured and their delivery timeline. Taiwan is purchasing four TPS-77s and five TPS-78s. The TPS-77s will begin arriving in 2026, while the TPS-78s will begin arriving in 2027. Both radar systems should be completely delivered by the end of 2028.

F-16 Block 70s
Taiwan’s first F-16 Block 70 aircraft rolled off the production line in March 2025, but the jets have not been flown to Taiwan yet. Taiwanese news sources reported that the first two aircraft would arrive in early October, around the time of the National Day holiday on October 10. The ROCAF has denied the press reports, but the Air Force Chief of Staff testified to the Legislative Yuan (LY) that he expects 10 aircraft to arrive before the end of the year.

Harpoon Coastal Defense System
The $2.37 billion sale of 100 ground-based Harpoon launchers, 25 radar vehicles, and 400 missiles is the largest asymmetric arms sale by dollar value in the backlog. In May 2025, the MND informed the LY that 5 launch vehicles and 1 radar vehicle had already been delivered. A press report from September 2025 indicates that Taiwan will take delivery of the first batch of ground-launched Harpoon missiles before the end of 2025. Assuming that there will be enough missiles to fully arm the five launchers, with four tubes apiece, this would be 20 total missiles.

MK-48 Heavyweight Torpedoes
Taiwan News, citing the MND’s budget request for 2026, reported in September that Taiwan will receive four training Mk-48 heavyweight torpedoes next year, with 14 additional torpedoes arriving in 2027 and 10 in 2028. There was a 2017 Congressional notification for 46 Mk-48s for $250 million, and it is not clear if these 28 total torpedoes represent a reduction in the original arms sale or if deliveries will continue past 2028. These torpedoes will arm Taiwan’s new class of indigenously produced submarines, which have run into delays.

MQ-9B Drones
Last month, we shared information from the 2026 MND budget request saying that two MQ-9B drones are expected to be delivered next year. Additional reporting from September clarifies that the two remaining drones will be delivered in 2028, and that all four will be the SeaGuardian variant of the MQ-9B, optimized for maritime reconnaissance.

Barracuda Missile Co-Production
The final major update from September 2025 was an announcement by Taiwan’s National Chung-Shan Institute of Science and Technology (NCSIST) that it will co-produce with Anduril Industries the Barracuda, a low-cost anti-ship missile. NCSIST claims that each missile will cost approximately $216,000 and be made in Taiwan. Little else is known about the Barracuda or the details of the co-production agreement, but if NCSIST and Anduril can indeed join forces to manufacture such missiles in Taiwan at scale, it would be a major positive development for Taiwan moving toward a sustainable asymmetric defense posture.

Co-production means that Taiwanese companies would produce American-designed weapons in Taiwan. Such agreements would require export licensing of sensitive US technology, which undergoes a complex and lengthy review and approval process. This may mean a slower up-front process, but successful co-production agreements between the United States and Taiwan would take pressure off an overburdened US defense industrial base while also giving the Taiwanese defense industry experience building more weapons. The Barracuda missile is not part of the backlog because it does not have an FMS case notified to Congress.

Conclusion
Although the dollar value of Taiwan’s arms sale backlog has not changed, 2025 has been a busy year for US-Taiwan arms sales. There is considerably more information available about delivery schedules and partial deliveries than last year, including much-faster-than-expected timelines for critical asymmetric capabilities like man-portable drones. We hope our methodological note explains our reasoning for not adjusting the backlog’s dollar value yet despite the partial delivery developments.

Taiwan Arms Backlog Data_September 2025 Download

Taiwan Arms Sale Backlog, August 2025 Update

Altius Deliveries and 2026 Delivery Schedules

By Joseph O’Connor and Eric Gomez

August featured a major development in arms sales to Taiwan, as US manufacturer Anduril announced the delivery of the first set of Altius drones to the MND, just six months after the initial contract was announced. In late August, the 2026 defense budget request was submitted to the Legislative Yuan, and included a schedule of incoming deliveries, including MQ-9B drones and Mk 48 heavyweight torpedoes.

The overall size of the U.S. arms sale backlog to Taiwan remains $21.54 billion. For arms sales valued at over $1 billion, deliveries in progress are marked in yellow-orange in our visualizations. Figure 1 shows the current composition of the arms sale backlog by weapon category. Table 1 shows an itemized list of arms sales in the backlog with the most recently available information about their status.

Altius UAV Delivery

On August 4, Anduril founder Palmer Luckey visited MND officials, presenting them with the first delivery of Altius-600M drones. This is especially significant as this sale was only notified to Congress in June 2024, just over a year ago, and as Liberty Times reported, likely set a record for the fastest delivery of weapons in the last twenty years. The Congressional notification gives a dollar value of $300 million for 291 drones.

However, the number in the first batch was reported as unspecified. Thus, we regard the Altius-600M sale as being partially but not fully delivered. Because the sale is under the $1 billion threshold, we have not adjusted the visualizations. The dollar value of the arms sale backlog will decrease once all the drones are in Taiwan. Regardless, the rapid speed of the initial Altius delivery to Taiwan is a positive development given the importance of these types of asymmetric capabilities in fending off a Chinese invasion.

2026 Defense Budget Request and Schedule of Delivery

On August 29, the 2026 defense budget was submitted to the Legislative Yuan (LY) by the Executive Yuan (EY) for review and debate. As United Daily News reported, the budget request also contained specifics about scheduled arms deliveries in the next year.

First, two MQ-9B drones (of four) for the ROCAF are expected next year. Backlog followers will recall that in May, an MND budget unfreezing report indicated that all four would be delivered in 2026 due to concerns about where they would be based.

Next, the remaining batch of five MS-110 reconnaissance pods (of six total) are scheduled to be delivered. The last update to this was in June, when a press report indicated that the pods would begin arriving in 2025, contradicting SIPRI’s claim that five had already been delivered.

Additionally, the report indicated that four Mark 48 heavyweight torpedoes of 46 will be delivered. Our last update to this sale was also in June, when we reported that delays to Taiwan’s indigenous submarine program may affect torpedo deliveries. We suspect that the 2026 torpedoes may be practice or training torpedoes.

Lastly, the budget report stated that all 14 Volcano anti-tank mining systems would be delivered by the end of next year. The last update to this was in September 2024, when a press report indicated delivery by 2026.

Another note from the budget report: Liberty Times reported that the budget also includes a request for 9 NASAMS launchers and 339 missiles for the ROCAF, worth $3.63 billion or NTD $110 billion. This was moved from the 2025 confidential budget to next year’s public budget.

Conclusion

The Altius delivery is extremely significant and a potential sign of things to come for future arms sales deliveries, especially lower-cost, asymmetric items. The updated schedules for 2026 deliveries are mixed, but completion of MS-110 pods and Volcano systems are welcome in reducing the $21 billion backlog.

Taiwan Arms Backlog Data_August 2025 Download

Taiwan Arms Sale Backlog, July 2025 Update

Second Batch of Abrams Tanks Arrives

By Eric Gomez and Joseph O’Connor

A second batch of Abrams tanks arrived in Taiwan in late July, but besides this development, July was quiet in terms of arms sales updates. From July 9-18, Taiwan’s military conducted its annual Han Kuang series of exercises, which featured several developments of note.

The Taiwan Security Monitor (TSM) dataset only removes an arms sale from the backlog when it is fully delivered. Therefore, the overall size of the U.S. arms sale backlog to Taiwan remains $21.54 billion. However, for arms sales valued at over $1 billion, deliveries in progress are marked in yellow-orange in our visualizations.. Figure 1 shows the current composition of the arms sale backlog by weapon category. Table 1 shows an itemized list of arms sales in the backlog with the most recently available information about their status.

Han Kuang Exercise

The biggest development in Taiwan security news in July was the annual Han Kuang exercise. Han Kuang is Taiwan’s largest and most highly publicized exercise. The 2025 iteration featured several notable changes from previous years. The TSM team conducted real-time open-source analysis of the Han Kuang exercise that can be found on our X account.

One of the most widely covered new aspects of the Han Kuang exercise was increased realism in engineering and logistics aspects of the exercise to better simulate wartime conditions. For example, military police troops practiced moving shoulder-fired Stinger missiles on Taipei’s underground metro system. Other aspects of improved realism in Han Kuang 2025 were the calling up of more reservists— 22,000 participated, a record high— and the integration of two civil defense drills that occur concurrently with Han Kuang but were previously kept separate.

Abrams Tank Delivery and Other Arms Sale Updates

The biggest piece of arms sales backlog news in July was the arrival of a second batch of 42 M1A2T Abrams tanks. Taiwan has now taken delivery of 80 Abrams tanks. The final batch of 28 tanks is expected to arrive in the first quarter of 2026, which seems likely given the successful on-time deliveries of the first two batches. The Abrams sale, valued at $2 billion, was originally notified to Congress in July 2019.

As a reminder, the TSM dataset does not reduce the overall dollar value of the backlog for partial deliveries, which is why there is no change in the backlog’s overall composition or dollar value from June 2025. The Abrams case, the third largest case by dollar value, has been a relatively smooth arms sale compared to other large cases in the backlog. Final delivery in early 2026 will bring the backlog’s overall value below the $20 billion threshold, assuming there are no new arms sales announced between now and then.

There were two other small developments in July worth mentioning:

First, at the end of the month, Raytheon was awarded a $3.5 billion contract to produce Lots 39 and 40 of AIM-120 Advanced Medium-Range Air-to-Air Missiles (AMRAAM), with a completion date in the third quarter of fiscal year 2031. The AMRAAM is one of the most popular U.S. arms sale items, as shown by the 19 foreign country customers mentioned in the contract award announcement. It is unclear when Taiwan will receive the missiles and how many missiles are being produced. Taiwan is currently waiting for delivery of 123 AMRAAM-ER missiles from a 2024 sale of National Advanced Surface-to-Air Missile Systems and 200 AIM-120C-8 missiles from a 2023 sale of various F-16 munitions.

Second, Taiwan’s Ministry of National Defense (MND) announced plans to purchase five types of commercial, off-the-shelf drones, with almost 50,000 to be purchased in 2026. Commercial drones have played a significant role in helping Ukraine stymie Russia and would be an important fixture of an asymmetric defense strategy for Taiwan. The MND has made welcome investments and efforts to expand its use of drones of various sizes and capabilities across the military, including purchasing approximately 1,000 small drones via U.S. arms sales (720 Switchblades and 291 ALTIUS drones).

While the overall value of the U.S. arms sales backlog to Taiwan did not change in July, the on-time delivery of a second batch of Abrams tanks is a good sign and a harbinger of a very large decrease in the backlog early next year.

Taiwan Arms Backlog Data_July 2025 Download

Taiwan Arms Sale Backlog, June 2025 Update

New MND Document Sheds Light on Arms Sale Status

By Eric Gomez

Taiwan’s Ministry of National Defense (MND) released a document in June 2025 that reports on the status of several US arms sales to the Legislative Yuan (LY). This is the third such document that I have found in my work on the arms sale backlog, with previous iterations released in June and October of last year. These MND reports are very valuable sources of information about the status of US arms sales to Taiwan. The June 2025 report does not contain any major surprises, but it does offer some additional bits of information.

There were no new arms sales to Taiwan notified to Congress in June 2025 and no reports of weapons deliveries either. The backlog remains valued at $21.54 billion, with just shy of $4.5 billion of this figure covering deliveries that have begun but are not finished. Figure 1 shows how the backlog is broken down between traditional capabilities, asymmetric capabilities, and munitions. Table 1 shows an itemized list of what arms sales are in the backlog, with information about their most recently known status.

Before delving into the MND report, I did want to highlight two other developments in June 2025.

Early in the month, Raytheon was awarded a $1.1 billion contract modification to produce several variants of approximately 2,000 AIM-9X air-to-air missiles, with over half earmarked for Foreign Military Sales (FMS) customers. The contract has a completion date of October 2028. The contract award announcement does not list specific FMS customers, but Taiwan is waiting for delivery of 100 AIM-9X Block IIs from an FMS case notified to Congress in September 2022. Updates on the AIM-9X case have been hard to find, but the contract award announcement is a good sign for Taiwan and many other countries.

The other backlogged arms sale that received an update in June 2025 is an FMS case for six MS-110 reconnaissance pods, which was notified to Congress in October 2020. SIPRI’s arms transfer dataset reports that almost all these pods were already delivered to Taiwan. However, a report by Taiwan’s Central News Agency in June 2025 that cites an MND source says that delivery of the MS-110s should begin 2025, though CNA did not provide an end date for delivery. This would suggest that SIPRI’s information is incorrect or out of date.

MND’s Arms Sale Report to the LY The three MND reports to the LY on US arms sales to Taiwan that I have translated follow a similar pattern. All the reports give a total number of active arms sales cases and mention how many of those cases are considered on time, delayed, or ahead of schedule. Most of the arms sale cases are on schedule, but there is no additional information on these cases. The overall number of cases mentioned in the MND report are slightly different from the overall number in our TSM dataset. I suspect, but cannot definitively prove with current data, that the MND does not include an arms sale on its list unless the sale has a signed Letter of Offer and Acceptance (LOA). A LOA contains a detailed payment schedule and expected delivery timeline for an FMS case and must be signed before the US military can enter a contract with the defense industry to produce new weapons systems.

There can sometimes be delays of one or two years between an FMS case being notified to Congress and a LOA being signed. So, it is possible that many recent arms sales to Taiwan (there were seven notified to Congress in 2024) are not included in MND’s list because their LOAs are being negotiated.

The June 2025 edition of the MND arms sales implementation report indicates that there are 18 arms sales currently in progress, with 15 on schedule, 2 delayed, and 1 ahead of schedule. The two delayed arms sales are AGM-154C Joint Standoff Weapon (JSOW) guided glide bombs and F-16 Block 70 fighter aircraft.

The JSOW sale was notified to Congress in 2017 and is one of the oldest arms sales in the backlog. The MND report says the bombs were supposed to be delivered in 2023 but limited production capacity and delays in testing pushed this back by three years to 2026. The JSOWs are supposed to arm Taiwan’s older F-16A/B fighter jets, which completed a major upgrade in late 2023. The three-year delay would mean a total gap of nine years between congressional notification and final delivery for the JSOWs. Taiwan is only purchasing around 50 bombs.

Delays in the new production F-16 Block 70 aircraft are less severe, but still noteworthy. I have previously written about the F-16 Block 70 delays for Taiwan Security Monitor. The June 2025 MND report does not contain any new information on the timeline for delivery. The MND is confident that all 66 aircraft will arrive in Taiwan before the end of 2026, despite the first aircraft only rolling off the assembly line in March 2025. In other words, the MND claims that final delivery of the F-16s will not be delayed despite delivery of the first aircraft occurring over a year behind schedule.

Finally, the June 2025 MND report echoes reporting from other sources on early delivery of the second batch of 18 HIMARS launchers, which are now expected in Taiwan before the end of next year—one year ahead of schedule. The 18 HIMARS were notified to Congress at the end of 2022, which would mean a little less than a four-year gap between notification and final delivery. By comparison, Taiwan’s first batch of 11 HIMARS took four years from notification (October 2020) to final delivery (November 2024), so Taiwan has a slightly shorter wait time for a larger order. It will probably take until 2027 for Taiwan to receive all the HIMARS munitions it is purchasing, but for the purpose of the backlog dataset once all launchers are in Taiwan I will consider the case to be delivered.

Taiwan Arms Backlog Data_June 2025 Download

Taiwan Arms Sale Backlog, May 2025 Update

Budget Unfreezing Reports Reveal New Information about Delivery Timelines

By Eric Gomez and Joseph O’Connor

The backlog of US weapons that have been sold but not delivered to Taiwan did not see any major shifts in the month of May. The backlog’s total value remains $21.5 billion, with deliveries of $4.4 billion—split roughly evenly between Abrams tanks and ground-launched Harpoon anti-ship missiles—in progress. See Figure 1 for a visualization of the backlog by weapons category and Table 1 for an itemized list.

Despite the lack of movement in the backlog’s dollar value, May was an important and illuminating month. Taiwan’s Ministry of National Defense (MND) released multiple reports to the Legislative Yuan (LY) with new information about several— though not all— of the backlogged arms sales.
One bit of housekeeping before diving into the MND reports: we have adjusted Table 1, the itemized list of backlogged arms sales. Instead of the rightmost column showing the change of status since the previous month (which mostly resulted in “No Change” month after month), it now shows the status of the arms sale based on the most current available information that TSM analysts have on hand. One of TSM’s readers suggested this change and it is a very good one, so please don’t be afraid to send (constructive) criticism to us in the future.

MND’s Budget Unfreezing Reports
There are some rather nasty politics happening in Taiwan this year. Elections in January 2024 produced a divided government. The Democratic Progressive Party’s (DPP) Lai Ching-te was elected president, but the DPP does not have a majority in the LY, holding 51 seats to the Kuomintang’s (KMT) 54 seats (2 legislators are independent, but caucus with the KMT) and the Taiwan People’s Party’s 8 seats.
The LY’s composition has led to some high profile legislative (and physical) fights, and the DPP is hoping that a recall effort will remove enough KMT lawmakers later this year to restore their majority and create a united government.
The silver lining of this messy political situation— at least, for those of us monitoring the Taiwan arms sale backlog— is the release of multiple budget unfreezing reports by the MND. During the LY’s defense budget process earlier this year, KMT lawmakers froze approximately $3 billion of 2025’s proposed defense spending (roughly 14 percent of the total budget) across 279 individual spending items. To unfreeze the money, the MND must submit short reports to the LY explaining the status of the frozen programs and providing information on how it plans to use funds in the upcoming year.
The MND released a flurry of these budget unfreezing reports in May 2025, and they contain very valuable information on the status of multiple US arms sales to Taiwan.

Stinger Missiles
There are two Foreign Military Sales (FMS) cases for Stinger missiles in the arms backlog for a combined total of 500 missiles and cost of $440 million. The Stinger cases have been particularly frustrating. Per a 2024 report from the MND to the LY, Taiwan had to re-sign an important document to facilitate the arms sale due to the Army wanting to add missiles to an FMS case originally advanced by the Navy. The original Navy case for 250 missiles was due to be completed by 2022, but as of May 2025, neither case has been fully resolved.
The May 2025 budget unfreezing report on the Stinger FMS case indicates that Taiwan should receive all its currently outstanding Stinger missiles and grip stocks before the end of 2025. The report also mentions that the MND is budgeting to purchase 585 additional launchers and 2,121 additional missiles, the bulk of both going to the Army. This massive Stinger buy has not yet received Congressional notification, but it should occur soon. The report mentions that the MND submitted a Letter of Request to the United States in the first quarter of 2025.

Harpoon Coastal Defense System (HCDS)
The largest asymmetric FMS case in the backlog is a purchase of 400 ground-launched Harpoon missiles, 100 launch vehicles, and 25 radar vehicles, valued at $2.37 billion. Earlier reporting from Taiwan’s press and the March 2025 annual update to SIPRI’s dataset on arms transfers suggested that components for this arms sale had started arriving in Taiwan, though there was some uncertainty about just how much was delivered.
The budget unfreezing report for the HCDS provides more details. Per the report, the first radar truck and five launch vehicles rolled off the production line in the first quarter of 2025. There was a bit of a gap between production and shipment to Taiwan. This first batch of vehicles arrived in Taiwan in late June 2025.

MQ-9B Unmanned Aircraft
A sale of four MQ-9B surveillance drones and two ground stations received Congressional notification in November 2020. When freezing funds for the MQ-9B purchase, legislators said they were concerned that the MND had plans to store all four aircraft in a single hangar.
The budget unfreezing report states that MND has adjusted its storage plan and will distribute the MQ-9Bs across more storage facilities to reduce their vulnerability to attack. The report anticipates that construction of the MQ-9B’s support facilities will be completed by the end of 2025. All four aircraft are expected to arrive in Taiwan sometime in 2026.

Field Information Communication System (FICS)
The $280 million FICS case had preciously little publicly available information after it was notified to Congress in December 2020, besides a press report from March 2022 claiming that delivery would occur sometime in 2025. The budget unfreezing report indicates that the FICS successfully finished system component testing earlier this year. Delivery of the first batch of systems is expected before the end of 2025, but it is not clear when the final delivery will occur.

High Mobility Artillery Rocket System (HIMARS)
Taiwan had two FMS cases for HIMARS—an initial buy of 11 launchers and Army Tactical Missile Systems (ATACMS) notified to Congress in 2020 and a plus-up of 18 additional launchers, guided rocket pods, and ATACMS in December 2022. In November 2024, the first batch of 11 launchers and several ATACMS arrived in Taiwan. The HIMARS cases are also cited as the only arms sale to Taiwan that is ahead of its original delivery schedule.
The budget unfreezing report provides more details about the pace of munitions deliveries for HIMARS. The report says that Taiwan should receive the remaining 18 launchers by the end of 2026, but deliveries of ATACMS and rocket pods could extend into 2027 given the large volume of munitions that Taiwan is purchasing. Additionally, Taiwan’s military successfully test-fired a HIMARS from its territory for the first time in May 2025.

Conclusion
Except for the secretive FICS, none of the information in the budget unfreezing reports was all that shocking or unexpected. While there are some deviations from earlier reported delivery timelines, none of these are significant. However, the budget unfreezing reports are a noteworthy example of transparency from the MND. This crop of reports is the result of a contentious political environment in Taiwan, but having a regular, publicly available reporting mechanism to keep the LY— and researchers— informed about arms sales delivery timelines would be valuable.
We at TSM will be tracking down and translating as many of these budget unfreezing reports as possible in the coming weeks.

Taiwan Arms Backlog Data May 2025 Download

Taiwan Arms Sale Backlog, April 2025 Update

In First 100 Days Trump Sells a Lot of Weapons, Just Not to Taiwan

By Eric Gomez

The Trump administration celebrated its 100^th day in office on April 30, 2025. Foreign Military Sales (FMS) were not one of the items that the administration trumpeted as it marked this milestone. That is not very surprising. While huge nerds like me and you reading this love to follow this stuff, arms sales are not usually high on any administration’s list of Things to Trumpet. But, because people like you and me exist, let’s look at Trump’s first 100 days of FMS cases.

Since this is Taiwan Security Monitor, let’s talk about Taiwan first. There were no FMS cases notified to Congress in Trump’s first 100 days, and there were no reports of major arms sales being delivered to Taiwan in April 2025. I assess the total dollar value of the backlog to remain at $21.54 billion— but there might be some good news for the backlog to report next month (I realize the irony of an arms sale backlog dataset suffering from a backlog of monthly posts). See Figure 1 for the breakdown of the backlog by weapons category and Table 1 for an itemized list.

There were two items of reporting out of Taiwan in April 2025 worth mentioning:

First, Taiwan’s Air Force announced that it would form an additional Patriot battalion as its inventory of interceptors grows. In December 2022, Congress received notification of an amendment to an older FMS case for Patriot systems. The amendment added 100 PAC-3 MSE interceptors and upgrades to launcher systems. Press reports and statements from Taiwan’s Ministry of National Defense have consistently said that they expect all 100 PAC-3 MSEs to arrive by the end of 2026, but the April 2025 reporting is the first time where new military units have been mentioned.

Second, Taiwan’s indigenous submarine program missed its planned start time for sea trials, which were supposed to run from April to September of 2025. The relevant FMS case in the backlog are two cases for heavyweight torpedoes worth a combined $430 million. Accurate data on the delivery timeline for the torpedoes has been hard to find, but if a delay in sea trials leads to a delay in the submarine entering service, then it would not be surprising to see a knock-on delay in the torpedoes. Taiwan Security Monitor will keep an eye on this and report any developments as soon as possible.

Trump’s First 100 Days of Arms Sales

April 2025 was an incredibly busy month for FMS cases being notified to Congress and the last day of the month coincided with Trump’s 100^th day in office. In April alone, Congress received notifications of 18 FMS cases, both new and modifications to older sales, totaling nearly $14 billion. Looking at the first 100 days of the administration, these numbers increase to 36 FMS cases worth almost $30 billion. The Taiwan Security Monitor team created two graphics to visualize this data. Figure 2.1 shows the number of FMS cases by region while Figure 2.2 shows the dollar value of the cases by region.

The Middle East has been the biggest beneficiary of new FMS cases in Trump’s first 100 days, holding the number one spot in terms of both the number of new cases (15) and the overall dollar value ($16.7 billion). Israel has been the single largest beneficiary of FMS cases by dollar value in this period, with $10.6 billion notified. Almost all the Israel arms sales were for munitions, such as bombs and missiles.

The Indo-Pacific and Europe have also received a substantial amount of FMS support from the Trump administration despite concerns about Trump’s treatment of US allies. Many of these FMS cases have been for munitions— the AIM-120 family of air-to-air missiles have been selling like hot cakes— but these also include some noteworthy major platforms such as a sale of 20 F-16s and related munitions to the Philippines for $5.5 billion and 175 Tomahawk missiles for the Netherlands for a little over $2 billion.

Given the processing times for FMS cases, it is possible that many of these cases being notified to Congress were already in the works before Trump took office, although as more time goes by this potential explanation becomes less likely. Trump was a big fan of arms sales in his first administration, however, and one of the Executive Orders in the first 100 days of his second administration is focused on reforming the arms sales process to speed up the delivery of weapons.

Conclusion

The world is still waiting to see what will be in the Trump administration’s first arms sale to Taiwan. As Taiwan Security Monitor has reported previously, there are rumors of a multi-billion-dollar package in the works, but both the dollar value and capabilities keep changing. Whatever ends up being in the eventual Taiwan arms sale will be an important bellwether, we at Taiwan Security Monitor will keep waiting for the announcement.

Taiwan Arms Backlog Data April 2025 Download

Taiwan Arms Sales Backlog, March 2025 Update

New SIPRI Data Sheds Light on Partial Deliveries

By Eric Gomez

The backlog of US arms sales announced but not delivered to Taiwan did not change in March 2025. As shown in Figure 1, the backlog remains $21.54 billion.

This lack of movement in the backlog’s topline number should not be confused with a lack of activity in March. New data from the Stockholm International Peace Research Institute (SIPRI) indicates partial delivery of a major arms sale occurred in 2024. Additionally, after a roughly two-year delay, Taiwan’s first F-16 Block 70/72 fighter aircraft rolled off the assembly line.

Sources: Defense Security Cooperation Agency: Press Release, US Congressional Record; “Major Arms Sales,”; DCSA Release; DCSA Major Arms Sales; DCSA Press Media TECRO; SIPRI Arms Transfers Database, Stockholm International Peace Research Institute; US Congressional Record; “Major Arms Sales,” Defense Security Cooperation Agency; “Defense News,” Ministry of National Defense, Republic of China; “Letter from the Ministry of National Defense, Submitting a Written Report on the ‘Implementation Status of US Arms Sales to Taiwan’ for the 2024 Budget Resolution,” Ministry of National Defense, June 12, 2024; and “Excerpt from ‘Ministry of National Defense 2024 Annual Budget Assessment Report’,” Ministry of National Defense, October 2023; and “Information on US Arms Sales to Taiwan,” Ministry of National Defense, October 30, 2024.SIPRI’s 2025 Arms Transfers Database

New SIPRI Dataset Reveals a Large Delivery in Progress

SIPRI released its annual update to the Arms Transfer Database in March 2025, which brings the data current as of the end of 2024. Tracking the delivery status of arms sales, to Taiwan or any other country, is a very difficult task. SIPRI’s dataset has been a valuable source of information for the Taiwan arms backlog project since its first publication in November 2023.

However, SIPRI’s data is also imperfect. The 2025 edition of the dataset, for instance, categorizes the sale of 11 HIMARS systems to Taiwan as partially delivered, despite the Ministry of National Defense (MND) confirming full delivery in late 2024. SIPRI is also missing two major Taiwan arms sales from its dataset: a plus-up of 18 additional HIMARS and 100 PAC-3 MSE interceptors for the Patriot air and missile defense system. In SIPRI’s defense, confirming the existence of these two arms sales was not easy. Because both cases were modifications to older arms sales, their notifications were published in the Congressional Record instead of the Defense Security Cooperation Agency’s website, which is a much more readily accessible source of information.

For the most part, SIPRI’s 2025 update comports with other information I collected in 2024 about the arms sale backlog, but there was one noteworthy development.

According to SIPRI’s dataset, Taiwan has started receiving components of the Harpoon Coastal Defense System or HCDS, a truck-mounted version of the Harpoon anti-ship missile. In October 2020, Congress received notification of a $2.37 billion sale of 100 HCDS launchers, 400 missiles, and 25 radar trucks. The HCDS case is the second-largest arms sale by dollar value in the backlog. In September 2024, Taiwan’s Liberty Times reported that some HCDS equipment had arrived in Taiwan, but I did not feel confident coding HCDS as partially delivered at that time because the Liberty Times reporting was not well detailed.

Based on SIPRI’s data, I feel confident in changing the HCDS sale to partially delivered. Like the Abrams tank sale, this partial delivery status is expressed by a different color in the Figure 1 pie chart. As a reminder, the dollar value of the Taiwan arms sale backlog will not be reduced until final delivery of the arms sale occurs because trying to estimate a dollar value for partial delivery would be too difficult and likely inaccurate. Partial delivery of arms sales worth more than $1 billion are displayed visually in Figure 1 and noted with yellow text in Table 1.

First New F-16 Rolls Off Delivery Line

The largest arms sale in the backlog, 66 F-16 Block 70/72s valued at $8 billion, also saw a major development in March 2025, as the first aircraft rolled off the assembly line. Delivery of the first F-16 is approximately two years behind schedule. An October 2024 MND report to the Legislative Yuan cited software problems and other development bottlenecks as the main culprit for delays.

Although the first F-16 has now finished assembly, I have elected to not mark this sale as being partially delivered. The October 2024 MND report and March 2025 reports from Taiwan’s Central News Agency and Taipei Times mention that there will be some gap between the new aircraft being produced and their delivery to Taiwan. This probably is because the aircraft will need to undergo some final flight testing and perhaps pilot training in the United States. Until the first F-16 Block 70/72 lands on Taiwan’s territory, I will not consider this sale to be partially delivered.

The Taiwan Security Monitor will continue keeping tabs on the F-16, HCDS, and all other arms sales in the backlog.

For the full dataset, click below:

Taiwan Arms Backlog Data March 2025 Download

Taiwan Arms Backlog, February 2025 Update

Early Trump Admin Arms Sales and Rumors of a Big Request from Taiwan

By Eric Gomez

There were no new US arms sales to Taiwan announced or delivered between January and February 2025. The backlog remains $21.54 billion.

Figure 1 shows how the backlog is divided among traditional capabilities, asymmetric capabilities, and munitions. Table 1 contains an itemized list of arms sales in the backlog.

Early Trump Arms Sales

February 2025 was a busy month in the world of foreign military sales (FMS) despite none going to Taiwan. The Trump administration notified Congress of nine FMS cases in February. Five of these cases, with a combined value of $10.4 billion, were for Israel.

In three of the Israel arms sales, the Trump administration bypassed the standard Congressional review period for FMS cases by stating an emergency existed justifying an immediate sale. Normally, Congress would have either 15 or 30 days—depending on the recipient country, Israel’s period is 15 days—to issue a joint resolution of disapproval to block the arms sale. The Trump administration’s invocation of an emergency is legal under the Arms Export Control Act, which governs FMS cases, but drew condemnation from several members of Congress arguing that the administration cut Congress out of politically sensitive sales.

Between inauguration day and the end of February, Middle Eastern countries have been the recipient of eight out of ten FMS cases (Japan and Romania have one sale apiece over the same period). It will be interesting to see if this trend continues. While there appears to be a consensus around reducing US focus on Europe, the administration’s approach to the rest of the world is not settled. Much of the administration’s senior foreign policy team has talked about focusing more on China, but recent arms sales and developments in March 2025 suggest more attention on the Middle East at least in the near term.

Rumors of a Large Taiwan Arms Sale

While there has been no official notification of the next US arms sale to Taiwan, the rumor mill was active in February. A Reuters report citing “sources familiar with the situation” said that Taiwanese and American officials were discussing a large arms sale with a price tag between $7 and $10 billion. The full scope of capabilities under discussion was not mentioned, but the Reuters article references HIMARS munitions and coastal defense cruise missiles. Taiwan is already waiting for delivery of these weapons from earlier arms sales, but both are asymmetric capabilities that would be good acquisitions for Taipei.

The last time the press reported on rumors of a Trump administration arms sale to Taiwan was in November 2024, shortly after the election. The Financial Times reported that Taiwan was thinking about making an overture to the incoming administration with a large weapons purchase. Traditional capabilities like F-35 fighter aircraft, E-2D airborne early warning and control aircraft, and retired Ticonderoga-class cruisers featured heavily in the November 2024 rumors, and the dollar figure was much higher at $15 billion.

With the caveat that none of the above information has been confirmed by either the US or Taiwanese governments, the change between the two reports is interesting. Traditional capabilities factored much more heavily in the earlier report, while the more recent report focused on asymmetric capabilities. Both packages would result in a sizable increase in the Taiwan arms sale backlog, but based on recent delivery timelines the February 2025 capabilities should arrive faster than the November 2024 capabilities.

Hopefully, as these negotiations unfold, Taiwan and the United States will keep moving closer to sales of asymmetric capabilities that are easier for Taiwan to afford and more likely to be delivered quickly. The appeal of traditional capabilities like F-35s or large surface warships is understandable, but given Taiwan’s levels of defense spending and longer delivery timelines buying more traditional capabilities would be an imprudent use of time and money.

Conclusion

February 2025 did not see any changes in the US arms sale backlog to Taiwan, but it did provide a peek into important issues that could impact the backlog. The Trump administration’s early emphasis on the Middle East for new arms sales raises questions about whether the administration’s actions will reflect its “China first” rhetoric. New rumors about a pending US arms sale to Taiwan suggest ongoing tension between Taiwan going all in on asymmetric defense versus securing Trump’s favor via the purchase of high-priced traditional capabilities.

For the full dataset, click below:

TSM – Taiwan Arms Backlog Data February 2025 Download

Taiwan Arms Sale Backlog, January 2025 Update

F-16 Delays and New Contracts

By Eric Gomez and Joseph O’Connor

The US arms sale backlog to Taiwan is slightly reduced from December 2024 thanks to new res earch conducted by the Taiwan Security Monitor team. There were no new foreign military sales (FMS) cases announced in January 2025 or announcements of full deliveries. However, we have removed a $332 million sale of 30mm ammunition from the backlog, which results in a new total backlog value of $21.54 billion.

Figure 1 shows how the arms sale backlog is divided across weapons categories. The 30mm ammunition FMS case was coded as Munitions in the dataset. The different color for the Abrams sale, coded as a Traditional weapon system, indicates that deliveries of the sale have started but have not finished.

The two other noteworthy developments in the arms backlog this month are new information about delivery delays for F-16 Block 70/72s and contract announcements for air defense systems that were notified to Congress in the last few months of the Biden administration.

Table 1 is an itemized list of FMS cases that are still included in the US arms sale backlog to Taiwan, with the 30mm ammunition sale marked in red to indicate its removal from the backlog.

30mm Ammunition FMS Case Removed from Backlog

In June 2023, Congress received notification of an FMS case for various types of 30mm ammunition valued at $332 million. Taiwan is currently developing an indigenous infantry fighting vehicle called the CM-34 Clouded Leopard that has a 30mm autocannon as its main armament. Increased production of the CM-34 will significantly drive up Taiwan’s demand for this type of munition.

After its initial notification to Congress, information about the 30mm FMS case has been scant. SIPRI’s Arms Transfer Database, our dataset’s primary source of information for weapons deliveries to Taiwan, does not include any information about the 30mm case. Out of an abundance of caution, previous editions of the arms backlog dataset included the 30mm sale. However, based on research conducted by Taiwan Security Monitor’s Joseph O’Connor, we are confident that this sale can be removed from the backlog.

Press reports from Taiwan indicate that in early 2024 Northrop Grumman was working with Taiwan’s Factory 205 to establish a production line for 30mm ammunition in Taiwan. It is not clear when the production run will be fully stood up, or how long it will run. Some components for the shells will be imported from the United States, so the coproduction agreement does not completely insulate Taiwan from US defense industry supply chains. However, moving production of 30mm ammunition to Taiwan will provide some insulation from delays and improve its long-term ability to provide for its own defense. For these reasons we have removed the 30mm FMS case from the backlog.

New Information on F-16 Delays

Delays of Taiwan’s 66 F-16 Block 70/72s, notified to Congress in August 2019 and valued at $8 billion, have increased yet again. Taiwan was originally supposed to receive two of the new aircraft sometime in 2023 with batches of the remaining aircraft arriving in 2024, 2025, and 2026 when delivery would be complete. In October 2024, Taiwan’s defense minister Wellington Koo acknowledged delays in the F-16 case but said that the first aircraft were expected to arrive before the end of 2024.

In January 2025, defense minister Koo provided another update on the F-16 delays, saying that the first aircraft will be delivered in March 2025, over a year behind schedule. Taiwanese press reports mentioned that 19 aircraft were currently on the production line, but it is not clear when these additional aircraft will arrive in Taiwan. The Ministry of National Defense has not revised the final delivery timeline of 2026, but sticking to that timeline will be difficult given the longer than expected wait for the first aircraft.

Contracts Announced for Air Defense Systems

The most significant asymmetric military capabilities that the Biden administration sold to Taiwan were three National Advanced Surface-to-Air Missile System (NASAMS) batteries and mobile L-band radar systems. Taiwan needs a densely layered air defense network that can deny China from achieving air superiority in a war. The NASAMS and radars are a valuable addition to Taiwan’s indigenous air defense capabilities. Congress received notification of both sales in October 2024.

According to a report by Taiwan’s Central News Agency, Taipei approved contracts for NASAMS and L-band radar systems with effective periods until the end of 2034 and 2030, respectively. It is possible that both arms sales will be delivered before the end of the contract’s effective period, so these dates are not an accurate estimate of the delivery timeline. However, the relatively short gap between congressional notification and contract posting suggests that both arms sales are moving relatively quickly through their program milestones. There is still plenty of time for things to go wrong, but the NASAMS and L-band radar sales are starting on the right foot.

Conclusion

The Taiwan arms sales backlog is off to a mixed start in 2025. A coproduction agreement for 30mm ammunition is a welcome development, and more such agreements would strengthen Taiwan’s ability to provide for its own defense needs. Contract announcements for NASAMS and mobile L-band radars soon after the announcement of these sales bodes well for on-time delivery of two important asymmetric capabilities.

However, growing delays in the F-16 program are a cause for concern and a reminder that traditional weapons systems like manned fighter aircraft are prone to production delays. We will continue to monitor the F-16 case and post timely updates on its progress.

For the full dataset, click below:

TSM – Taiwan Arms Backlog Data_January 2025 Download