By Hans M. Kristensen, Matt Korda, Eliana Johns, Mackenzie Knight-Boyle
The United States has embarked on a wide-ranging nuclear modernization program that will ultimately see every nuclear delivery system replaced with newer versions over the coming decades. In this issue of the Nuclear Notebook, we estimate that the United States maintains a stockpile of approximately 3700 warheads—an unchanged estimate from the previous year. Of these, only about 1770 warheads are deployed, while approximately 1930 are held in reserve. Additionally, approximately 1342 retired warheads are awaiting dismantlement, giving a total inventory of approximately 5042 nuclear warheads. Of the approximately 1770 warheads that are deployed, 400 are on land-based intercontinental ballistic missiles, roughly 970 are on submarine-launched ballistic missiles, 300 are at bomber bases in the United States, and approximately 100 tactical bombs are at European bases. The Nuclear Notebook is researched and written by the staff of the Federation of American Scientists’ Nuclear Information Project: director Hans M. Kristensen, associate director Matt Korda, and senior research associates Eliana Johns and Mackenzie Knight-Boyle.
This article is freely available in PDF format in the Bulletin of the Atomic Scientists’ digital magazine (published by Taylor & Francis) at this link. To cite this article, please use the following citation, adapted to the appropriate citation style: Hans M. Kristensen, Matt Korda, Eliana Johns, and Mackenzie Knight-Boyle. 2026. “United States nuclear weapons, 2026.” Bulletin of the Atomic Scientists, 82(2): 119–150. DOI: https://doi.org/10.1080/00963402.2026.2633029
To see all previous Nuclear Notebook columns in the Bulletin of the Atomic Scientists dating back to 1987, go to https://thebulletin.org/nuclear-notebook/.
As of February 2026, we estimate that the US Department of Defense maintains an estimated stockpile of approximately 3700 nuclear warheads for delivery by ballistic missiles and aircraft. Most of the warheads in the stockpile are not deployed but rather stored for potential upload onto missiles and aircraft as necessary. We estimate that approximately 1770 warheads are currently deployed, of which roughly 1370 strategic warheads are deployed on ballistic missiles and another 300 at strategic bomber bases in the United States. An additional 100 tactical bombs are deployed at air bases in Europe. The remaining warheads—approximately 1930—are in storage as a so-called “hedge” against technical or geopolitical surprises. Several hundred of those warheads are scheduled to be retired before 2030 (see Table 1).
While the majority of the United States’ warheads comprise the Department of Defense’s military stockpile, retired warheads under the custody of the Department of Energy awaiting dismantlement constitute a “significant fraction” of the United States’ total warhead inventory (US Department of Energy 2024b, F-6). Dismantlement operations include the disassembly of retired weapons into component parts that are then assigned for reuse, storage, surveillance, or additional disassembly and subsequent disposition (US Department of Energy 2023b, 2–11).
The pace of warhead dismantlement has slowed significantly in recent years: While the United States dismantled on average more than 1000 warheads per year during the 1990s, in 2023 it dismantled only 69 warheads—the lowest number since the 1990s (National Nuclear Security Administration 2024a). According to the Department of Energy, “[d]ismantlement rates are affected by many factors, including weapon system complexity, availability of qualified personnel, equipment, facilities, logistics, policy and directives, and legislative requirements” (US Department of Energy 2024a, 2–14). The US Department of Energy stated in April 2023 that it “was on pace to complete the dismantlement of all warheads retired before Fiscal Year (FY) 2009 [Sep. 2008] by the end of FY 2022 [Aug. 2022]” but that the COVID-19 pandemic “delayed the dismantlement of a small number of these retired warheads until after FY 2022 [Aug. 2022]” (US Department of Energy 2023a, 2–12). The FY 2025 Stockpile Stewardship and Management Plan reported that the Pantex Plant—where all warhead assembly and disassembly activities take place—surpassed its FY 2023 dismantlement goals and increased its staffing to support its FY 2024 commitments. It also reportedly completed the dismantlement of all remaining W84 warheads that had previously been in the queue—a process that took approximately 15 years from start to finish for the entire stockpile of 400 warheads (Kristensen 2010; US Department of Energy 2024a, 2–14).
Warhead dismantlement and disposition is an important process for the National Nuclear Security Administration (NNSA), as the new warheads that the United States is building rely on critical components from warheads that are currently awaiting retirement and eventual dismantlement. For example, the new B61-12 and B61-13 gravity bombs utilize modified versions of the physics packages used in the current B61-4 and B61-7 gravity bombs, respectively.
Based on these timelines and recent dismantlement rates, we estimate that the United States possesses approximately 1342 retired—but still intact—warheads awaiting dismantlement, giving a total estimated US inventory of approximately 5042 warheads.
The US nuclear weapons are thought to be stored at an estimated 24 geographical locations in 11 US states and five-six European countries (Kristensen and Korda 2019, 124). The number of locations will increase over the next decade as nuclear storage capacity is added to three air bases in the United States—Ellsworth, Dyess, and Barksdale—and two in the United Kingdom—RAF Lakenheath and RAF Marham. The location with the most nuclear weapons by far is the large Kirtland Underground Munitions and Maintenance Storage Complex south of Albuquerque, New Mexico. Most of the weapons in this location are retired weapons awaiting dismantlement at the Pantex Plant in Texas. The state with the second-largest inventory is Washington, which is home to the Strategic Weapons Facility Pacific and the ballistic missile submarines at Naval Submarine Base Kitsap. The submarines operating from this base carry more deployed nuclear weapons than any other base in the United States.
The United States has embarked on an ambitious plan to overhaul its nuclear weapons arsenal and command and control systems over the next three decades though the modernization effort has faced significant political, financial, and logistical challenges. Based on the Congressional Budget Office’s (2017) estimate, the modernization effort—combined with the costs of fielding and operating existing systems—was expected to cost $1.2 trillion over the next 29 years (Congressional Budget Office 2017). In its most recent estimate, the Congressional Budget Office projected these costs to reach $946 billion over the 2025 to 2034 period alone (Congressional Budget Office 2025a). Historical trends and chronic delays to the modernization program indicate that the price tag is likely to continue increasing over time.
In addition to the ongoing warhead modernization programs, the United States is also starting to consider how follow-on warhead programs will ultimately shape the US force posture. A new nuclear sea-launched cruise missile is being developed to enter the force in the early-2030s. Moreover, in 2024, the Nuclear Weapons Council approved two studies on non-ballistic reentry vehicles and hard and deeply buried targets (US Department of Energy 2024a, 5–14). The FY26 Congressional Justification sought a budget increase to fully fund the concept and assessment phase for two potential new warheads: one from the Next Generation Reentry Capabilities (NGRC) program (provisionally named WXX), as well as “a variety of Hard and Deeply Buried Target (HDBT) defeat efforts” (US Department of Energy 2025, 213, 218). One of these appears to be a “prototype air-delivered nuclear delivery system…to address a United States Strategic Command capability gap…to close this gap in the near term.” The prototype will be developed using F-15E and B-2 aircraft starting in 2026, examine several nuclear warhead options, and be completed in 2029 (US Department of Defense 2025c). The language suggests the prototype may be powered.
In 2023, multiple governmental advisory commissions published reports intended to influence the US nuclear posture. The US State Department’s International Security Advisory Board report on “Deterrence in a World of Nuclear Multipolarity” advised the United States to pursue competition with Russia and China “without accelerating arms race instability or risking runaway competition” (US State Department 2023b). In contrast, the Congressionally mandated report on “America’s Strategic Posture,” published in October 2023, included a broad range of recommendations for the United States to prepare to increase the number of deployed warheads, as well as to scale up its production capacity of bombers, air-launched cruise missiles, ballistic missile submarines, non-strategic nuclear forces, and warheads (US Strategic Posture Commission 2023). It also called for the United States to deploy multiple warheads on land-based intercontinental ballistic missiles (ICBMs) and consider adding road-mobile ICBMs to its arsenal.
While neither report represents official US government policy, the Strategic Posture Commission report’s status as a bipartisan document has been particularly useful for nuclear advocates to push for additional nuclear weapons (The Heritage Foundation 2023; Hudson Institute 2023; Thropp 2023). The second Trump administration has already attempted to adopt some of the more hawkish policies included in the Strategic Posture Commission and other non-governmental nuclear advisory papers. For example, some have advocated that the United States prepare to resume nuclear testing—something no country aside from North Korea has done since the 1990s—primarily as a demonstration of resolve (Peters 2025). In October 2025, Donald Trump made several statements indicating a desire to resume nuclear testing, followed by affirmation from Secretary of Defense Pete Hegseth (Price and Ceneta 2025). During his confirmation hearing, the Trump administration’s nominee for US STRATCOM Commander, Vice Admiral Richard Correll, cautioned that Trump was probably not referring to explosive nuclear testing (Hitchens 2025), although this was not confirmed by the president. After the confusion created by Trump’s statement, the US Department of State published US Intelligence that China had conducted very small explosive tests using decoupling to reduce seismic signals (DiNanno 2026).
Research methodology and confidence
The analyses and estimates made in the Nuclear Notebook are derived from a combination of open sources: (1) state-originating data (e.g. government statements, declassified documents, budgetary information, military parades, and treaty disclosure data); (2) non-state-originating data (e.g. media reports, think tank analyses, and industry publications); and (3) commercial satellite imagery. Because each of these sources provides different and limited information that is subject to varying degrees of uncertainty, we crosscheck each data point by using multiple sources and supplementing them with private conversations with officials whenever possible.
Collecting and analyzing accurate information about US nuclear forces is significantly less challenging than for most other countries, as the United States is the most transparent nuclear-armed state. To that end, we assess that the estimates included in this Nuclear Notebook come with a relatively high degree of confidence.
The United States is one of only a small handful of countries that has published data about the exact size of its nuclear stockpile. While this data is not released annually and largely depends upon the whims of the administration in power, in 2024, the US government responded positively to a declassification request made by the Federation of American Scientists and disclosed the size of the stockpile and number of annually dismantled warheads through September 2023 (National Nuclear Security Administration 2024a). The disclosure revealed that as of September 2023, the United States’ nuclear stockpile included 3748 warheads—only 40 more than our previous estimate of 3708 (Kristensen et al. 2024; National Nuclear Security Administration 2024a). We estimate that the stockpile will continue to decline slightly over the next decade as modernization programs consolidate the remaining warheads.
In addition, the United States also releases highly detailed assessments and reports relating to its nuclear forces, including the NNSA’s Stockpile Stewardship and Management Plan, budgetary justification documents, and environmental impact statements, among others. Government officials are also legally responsive to checks and balances, particularly Congress, which regularly asks for programmatic and budgetary updates on nuclear weapons programs. These checks are supported by robust watchdog, civil society, and media organizations, including government-funded agencies like the Government Accountability Office and the Congressional Budget Office, investigative journalists, and nongovernmental organizations that report on and critique government programs and plans.
We generally rely on official sources and images—as well as commercially or freely available satellite imagery—to analyze the United States’ nuclear arsenal and, whenever possible, try to corroborate the credibility of any unofficial claims with multiple sources. Satellite imagery can be particularly useful in monitoring construction at military facilities, as well as identifying which types of missiles, vessels, or aircraft are present at bases. In certain cases, useful imagery about nuclear systems can also be obtained through social media posts—both from military and civilian accounts—and can be used in conjunction with satellite imagery for more concrete analysis.
Finally, the United States is party to a bilateral arms control treaty with Russia—the New Strategic Arms Reduction Treaty (New START)—that until recently produced biannual datasets of deployed strategic nuclear forces. Russia suspended its participation in New START in February 2023, and in response the United States has not published any aggregate numbers since May 2023, when it declared that it had 1419 warheads attributed to 662 deployed ballistic missiles and heavy bombers as of March 1, 2023 (US State Department 2023a). The 2022 Nuclear Posture Review stated that “[t]he United States will field and maintain strategic nuclear delivery systems and deployed weapons in compliance with New START Treaty central limits as long as the Treaty remains in force” (US Department of Defense 2022a, 20), and the second Trump administration has so far adhered to this plan.
The New START warhead numbers reported by the US State Department differ from the estimates presented in this Nuclear Notebook for several reasons. The New START counting rules artificially attribute one warhead to each deployed bomber, even though US bombers do not carry nuclear weapons under normal circumstances. Moreover, the Nuclear Notebook counts as deployed all weapons stored at bomber bases that can quickly be loaded onto the aircraft, as well as nonstrategic nuclear weapons at air bases in Europe. This provides a more realistic picture of the status of US-deployed nuclear forces than the treaty’s artificial counting rules.