Treaty Structure: The Treaty between the United States of America and the Russian Federation on Measures for the Further Reduction and Limitation of Strategic Offensive Arms, also known as the New START Treaty, enhances U.S. national security by placing verifiable limits on all Russian deployed intercontinental-range nuclear weapons. The United States and the Russian Federation have agreed to extend the treaty through February 4, 2026.

Strategic Offensive Limits: The New START Treaty entered into force on February 5, 2011.  Under the treaty, the United States and the Russian Federation had seven years to meet the treaty’s central limits on strategic offensive arms (by February 5, 2018) and are then obligated to maintain those limits for as long as the treaty remains in force.

Aggregate Limits

Both the United States and the Russian Federation met the central limits of the New START Treaty by February 5, 2018, and have stayed at or below them ever since. Those limits are:

  • 700 deployed intercontinental ballistic missiles (ICBMs), deployed submarine-launched ballistic missiles (SLBMs), and deployed heavy bombers equipped for nuclear armaments;
  • 1,550 nuclear warheads on deployed ICBMs, deployed SLBMs, and deployed heavy bombers equipped for nuclear armaments (each such heavy bomber is counted as one warhead toward this limit);
  • 800 deployed and non-deployed ICBM launchers, SLBM launchers, and heavy bombers equipped for nuclear armaments.

Fact Sheet: New START Treaty Aggregate Numbers of Strategic Offensive Arms (May 13, 2023)

New START limits all Russian deployed intercontinental-range nuclear weapons, including every Russian nuclear warhead that is loaded onto an intercontinental-range ballistic missile that can reach the United States in approximately 30 minutes. It also limits the deployed Avangard and the under development Sarmat, the two most operationally available of the Russian Federation’s new long-range nuclear weapons that can reach the United States. Extending New START ensures we will have verifiable limits on the mainstay of Russian nuclear weapons that can reach the U.S. homeland for the next five years. As of the most recent data exchange on September 1, 2020, the Russian Federation declared 1,447 deployed strategic warheads. The Russian Federation has the capacity to deploy many more than 1,550 warheads on its modernized ICBMs and SLBMs, as well as heavy bombers, but is constrained from doing so by New START.

Force Structure: Each Party has the flexibility to determine for itself the structure of its forces subject to the central limits. The New START Treaty gives the United States the flexibility to deploy and maintain U.S. strategic nuclear forces in a way that best serves U.S. national security interests.

Verification and Transparency: The treaty contains detailed procedures for the implementation and verification of the central limits on strategic offensive arms (discussed above) and all treaty obligations. These procedures govern the conversion and elimination of strategic offensive arms, the establishment and operation of a database of treaty-required information, transparency measures, a commitment not to interfere with national technical means of verification, the exchange of telemetric information, the conduct of on-site inspection activities, and the operation of the Bilateral Consultative Commission (BCC).

New START Treaty Verification Measures

Measures Description
Onsite Inspections The treaty provides for 18 on-site inspections per year for U.S. and Russian inspection teams:  Type One inspections focus on sites with deployed and non-deployed strategic systems (up to 10 per year), and Type Two inspections focus on sites with only non-deployed strategic systems (up to 8 per year).  Permitted inspection activities include confirming the number of reentry vehicles on one deployed ICBM or SLBM per Type One inspection, counting nuclear weapons onboard or attached to deployed heavy bombers, counting numbers of non-deployed ICBMs and SLBMs, confirming weapon system conversions or eliminations are conducted in the way proposed, and confirming facility eliminations.
Warheads Loaded on Specific Strategic Delivery Vehicles During inspections of deployed strategic weapon bases/facilities, each side must disclose how many warheads are on each delivery vehicle based at the inspected base, and the inspecting country has the right to inspect the loading on one delivery vehicle (chosen by the inspecting country) to confirm the declaration is accurate.
Biannual Data Exchanges Each country provides the other with a declaration of its deployed strategic delivery vehicles, launchers and warheads, including:  a breakdown of warhead numbers deployed across the three types of delivery vehicles; a breakdown of how many strategic delivery vehicles and warheads are deployed at each declared base.  A substantial amount of information is also provided in the periods between biannual exchanges, via treaty-required notifications (see below).
Telemetric Information To enhance transparency, the Parties annually exchange telemetric information on a parity basis, for up to five ICBM and SLBM launches per year.  These measurements of various technical parameters are made to monitor missile performance during ICBM and SLBM flight tests.
Strategic Delivery Vehicle and Launcher Notifications The treaty provides for rolling notifications regarding the status (i.e., deployed/non‑deployed) and basing or facility assignment of all strategic delivery vehicles and launchers.  Notifications for dispersal of mobile ICBMs and ballistic missile submarines (SSBN) patrols are not required.
New Types, New Variants, and New Kinds of Treaty‑Accountable Systems Declaration and exhibition of new types and new variants of treaty‑accountable systems that enter service.  The system would then be subject to data declarations, notifications, and inspections under the treaty.  The treaty also provides both sides the opportunity to raise new kinds of Strategic Offensive Arms in the BCC and seek their inclusion under New START.
Bilateral Consultative Commission The treaty establishes the BCC as a compliance and implementation body that meets at least twice each year unless otherwise agreed. (Note: Due to COVID, the Parties did not convene any BCC meetings in 2020, but continued discussion of BCC matters in diplomatic channels).  Compliance or implementation questions may be raised by either Party in the BCC.
Ballistic Missile Launches The treaty provides for pre‑launch notifications of the launch of treaty‑accountable ballistic missiles (this is also consistent with both Parties’ obligations under their 1988 Ballistic Missile Launch Notification Agreement).
Non‑Interference with National Technical Means (NTM) The treaty permits the use of national technical means of verification (e.g. satellites) in a manner consistent with international law, and contains explicit provisions that prohibit interference with NTM and the use of concealment measures that may impede monitoring by NTM.
Unique Identifiers Each ICBM, SLBM, and heavy bomber is assigned a unique identifier, which is included in the applicable notifications and may be confirmed during inspections.

The New START Treaty’s verification provisions enable the United States to assess Russian compliance with the treaty and give us a vital window into Russian intercontinental-range nuclear forces and operations.  Without the New START Treaty’s verification measures, there would be a decrease in U.S. knowledge of Russian nuclear forces.  Over time we would have less confidence in our assessments of Russian forces and would have less information upon which to base decisions about U.S. nuclear forces.

Data Exchanges and Notifications:  The sides exchange data on the numbers, locations, and technical characteristics of weapons systems and facilities that are subject to the treaty and provide each other with regular notifications and updates.  These notifications engender unique insight into the Russian Federation’s nuclear forces that would otherwise be unavailable.  Without the treaty, the United States would be left with less awareness of and reliable information on the Russian Federation’s ICBMs, SLBMs, and heavy bombers.

Information Exchanged under the New START Treaty

Type of Information Under New START
New missiles entering the force Each party provides 48‑hours notice before a solid-fueled ICBM leaves a production facility
Basing location of treaty-accountable missiles Each party provides notification of its associated base or facility
Status change for missiles Each party provides notification when missiles become deployed or non‑deployed and sent to declared facilities.
Advance Notice of Major Strategic Exercises Each party provides notification at least 2 weeks prior to a major strategic exercise involving heavy bombers and notifies again within 2 days following the exercise’s conclusion.
Elimination and conversion Notification of the elimination of treaty‑accountable systems or conversion to non‑nuclear or non‑accountable status.  For example:  removal of fuel from ICBMs, and leaving the eliminated system in view of NTM for 60 days.

Implementation: The information provided through the treaty’s implementation contributes to reducing the risk of strategic surprise, mistrust, and miscalculations that can result from excessive secrecy or decisions based on worst-case assumptions.  Since the New START Treaty’s entry into force, as of February 1, 2023, the two parties have conducted:

  • 328 on-site inspections,
  • 25,449 notifications exchanged,
  • 19 meetings of the Bilateral Consultative Commission, and
  • 42 biannual data exchanges on strategic offensive arms subject to the treaty.

Treaty Duration: The treaty’s original duration was 10 years (until February 5, 2021), with the option for the Parties to agree to extend it for up to an additional five years. The United States and Russian Federation agreed on a five-year extension of New START to keep it in force through February 4, 2026. The treaty includes a withdrawal clause that is standard in arms control agreements.

Russian Compliance:  Although the United States has raised implementation-related questions and concerns with the Russian Federation through diplomatic channels and in the context of the BCC, the United States has determined annually since the treaty’s entry into force, across multiple administrations, the Russian Federation’s compliance with its treaty obligations.

U.S. Compliance:  The United States is in compliance with its New START obligations.  The Russian Federation has criticized U.S. procedures used to convert B-52H heavy bombers and Trident-II SLBM launchers.  The United States stands by its conversion procedures, which render the converted SLBM launchers and heavy bombers incapable of employing nuclear weapons thereby removing them from accountability under the treaty.

What is the difference between a “Type One” and a “Type Two” inspection?

The New START Treaty provides for 18 on-site inspections per year. There are two basic types of inspections. Type One inspections focus on sites with deployed and non-deployed strategic systems; Type Two inspections focus on sites with only non-deployed strategic systems. Permitted inspection activities include confirming the number of reentry vehicles on deployed ICBMs and deployed SLBMs, confirming numbers related to non-deployed launcher limits, counting nuclear weapons onboard or attached to deployed heavy bombers, confirming weapon system conversions or eliminations, and confirming facility eliminations. Each side is allowed to conduct ten Type One inspections and eight Type Two inspections annually.

New START at a Glance

Treaty Year Eleven
United States
Total Inspections Conducted  0
Total Inspections Allowed 18
Inspections Remaining 18
Russian Federation
Total Inspections Conducted  0
Total Inspections Allowed 18
Inspections Remaining 18
Total Notifications Exchanged


Current as of 01 June 2023


U.S. Department of State

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