Treaty Research

This guide describes resources and methods for locating and updating treaties of the United States and other countries.

Status Information & Updating (U.S. Treaties)

Table of Contents

Once you have located the text of a treaty or agreement, you will need to determine its current status. This can be a challenging task, as status information is always evolving, and the relevant research tools continue to migrate from print to electronic formats.  Use the resources described below to determine the ratification status of treaties, whether or not treaties and other international agreements have entered into force or been amended after entering into force, and to identify treaties that never entered into force.

Ratification Status

  • Treaty Action in the Senate (U.S. Senate Website)
    This page on the U.S. Senate's website allows you to track the progress of treaties submitted for ratification during the current Congress.  It also provides an historical overview of the Senate's role in treaty ratification, a list of treaties rejected by the Senate, and annual summaries of treaty actions taken by the Senate from 1947-present.
  • List of Treaties Pending Before the Senate  (U.S. State Department Website)
    The State Department's list includes treaties submitted for ratification during the current Congress as well as treaties submitted to the Senate during prior Congresses that remain pending and un-ratified.  Note that un-ratified treaties remain pending before the Senate at the end of a congressional term, unless they are withdrawn by the president.
  • Senate Treaty Documents (
    Treaties submitted to the Senate for ratification are first published as Senate Treaty Documents.  In addition to the full text of a treaty, a Senate Treaty Document also may include letters of transmittal from the president and the secretary of state, along with other supporting or explanatory documentation. has all Senate Treaty Documents from 1975-present, as well as selected treaty documents from 1949-1974.  Search by keyword or by document number.  Or use the filters on the left to browse by congress number.  Note:  The record for each treaty document on provides a summary of all Senate actions taken to date with respect to the treaty in question.

Entry Into Force, Declarations, Reservations & Subsequent Amendments (Protocols)

  • Treaties in Force (TIF)
    To determine whether or not a treaty or agreement has entered into force for the U.S., consult the most recent 2020 edition of TIF and the 2022 supplement to the 2020 edition, which are available for download from the State Department website.  Multilateral treaties are arranged alphabetically by subject in Section 2 of TIF

    For each multilateral treaty, TIF provides the date of entry into force for the treaty and the date of entry into force for the U.S., as well as a link to the depositary for the treaty.  Follow the link to the depositary website to find out which other countries are parties to the treaty and whether the U.S. or other parties ratified the treaty subject to any declarations or reservations.  TIF also provides information about subsequent amendments made to treaties already in force.
  • Treaty Actions
    This online publication from State Department's Office of Treaty Affairs used to provide monthly updates on the status of treaties and other international agreements, including dates of entry into force and amendments made to treaties and agreements already in force.  It was last published in November of 2012, and there is no indication that regular publication will resume.  Nevertheless, it is still useful for historical research on the status of treaties.  This content was previously published in print under the following titles:
  • Status Lists and Recent Actions for Multilateral Treaties for Which the U.S. Is the Depositary
    The State Department maintains this online resource for multilateral treaties for which the U.S. is the depositary.  (The depositary acts as the official custodian of the treaty text, as well as any subsequent amendments or protocols, and is responsible for compiling an up-to-date list of signatories and ratifications.)
  • Multilateral Treaties Deposited with the Secretary-General (MTDSG)
    This U.N. database is an excellent sources for status information and updates on multilateral treaties, whether or not the U.S. is a party.  Coverage is limited to the 560+ multilateral treaties that have been deposited with the U.N. secretary-general.  Treaties are arranged chronologically by subject matter, with each chapter of the MTDSG corresponding to a particular subject.
  • Subject-Specific Online Treaty Collections
    Subject-specific online treaty collections also can be good sources for status information and updates on multilateral treaties, whether or not the U.S. is a party.  Click on the link above for a directory of subject-specific treaty collections that are accessible online.
  • State Department -- Office of Treaty Affairs
    As a last resort, if all else fails, contact the State Department's Office of Treaty Affairs by email ( for clarification on the status of a particular treaty or agreement.

Treaties That Never Entered Into Force

  • Unperfected Treaties of the United States of America, 1776-1976.  Call No. KZ236 .A5
    This 9-volume set includes the texts of treaties concluded by the U.S. between 1776 and 1976 that, for various reasons, never entered into force.  Content is arranged chronologically by date of signature.  Each volume has its own subject index.  The final volume includes a cumulative subject index.
  • Treaties Rejected by the U.S. Senate
    The U.S. Senate website maintains this webpage, which includes a list of all treaties submitted for ratification that were rejected by the Senate in a recorded vote.  The treaties are listed in chronological order, along with the outcome of the vote.  Note that this list only includes treaties that have been voted upon and rejected.  It does not include treaties that have been submitted for ratification but never put to a vote or subsequently withdrawn.