List of parties to the Biological Weapons Convention


The list of parties to the Biological Weapons Convention encompasses the states which have signed and ratified or acceded to the Biological Weapons Convention, a multilateral treaty outlawing biological weapons.
On 10 April 1972, the BWC was opened for signature. The Netherlands became the first state to deposit their signature of the treaty that same day. The treaty closed for signature upon coming into force on 26 March 1975 with the deposit of ratification by 22 states. Since then, states that did not sign the BWC can only accede to it.
A total of 197 states may become members of the BWC, including all 193 United Nations member states, the Cook Islands, the Holy See, the State of Palestine and Niue. As of May 2025, 189 states have ratified or acceded to the treaty, most recently the Kiribati in May 2025. Additionally, the Republic of China, which is currently only recognized by, deposited an instruments of ratification of the BWC with the United States government prior to the US's decision to switch their recognition of the sole legitimate government of China from the Republic of China to the People's Republic of China. A further four states have signed but not ratified the treaty.
Several countries made reservations when ratifying the agreement declaring that it did not imply their complete satisfaction that the BWC allows the stockpiling of biological agents and toxins for "prophylactic, protective or other peaceful purposes", nor should it imply recognition of other countries they do not recognise.

States Parties

According to the treaties database maintained by the United Nations Office for Disarmament Affairs, as of May 2025, 189 states have ratified or acceded to the BWC.
Multiple dates indicate the different days in which states submitted their signature or deposition, varied by location. This location is noted by: for London, for Moscow, and for Washington D.C.
StateSignedDepositedMethod
Afghanistan|2013dts|1972|Apr|10dts|1975|Mar|26

State with limited recognition, abiding by treaty

The Republic of China, which is currently only recognized by, deposited their instruments of ratification of the BWC with the United States government prior to the US's decision to switch their recognition of the sole legitimate government of China from the Republic of China to the People's Republic of China in 1971. When the PRC subsequently ratified the treaty, they described the ROC's ratification as "illegal". The ROC has committed itself to continue to adhere to the requirements of the treaty, and the United States has declared that they still consider them to be "bound by its obligations".
StateSignedDepositedMethod
Republic of China

Signatory states

The following four states have signed, but not ratified the BWC.
StateSignedRatification status
Egyptdts|1972|Apr|10

Non-signatory states

The following four UN member states have neither signed nor ratified the BWC.
StateRatification status
Chadefn|In June 2017, Parliamentarians for Global Action reported that Chad's National Assembly had recommended that the government ratify the agreement.

Succession of UK dependent territories

When the United Kingdom ratified the BWC in 1975, it made a territorial declaration stating in part that the treaty would be applied:
This declaration bound its dependent territories of Dominica, Kiribati, Tuvalu and Vanuatu to the terms of the convention.
Following their subsequent independence, their status with regards to the convention was initially unclear. According to the Vienna Convention on Succession of States in respect of Treaties, "newly independent states" receive a "clean slate", such that they do not automatically inherit the treaty obligations of their former colonial power, but may in most circumstances succeed to multilateral treaties to which their former colonizers were a party to without the consent of the other parties. All four states eventually formally submitted instruments of accession or succession to the convention.

Dominica

After Dominica's independence in 1978, the Prime Minister of Dominica sent a note to the Secretary-General of the United Nations stating that:
The Government of Dominica later stated that it did not consider itself bound by the Convention. However, Dominica was listed as a state party to the BWC in documents from the Meetings of the States Parties to the BWC. The UK Treaty Office did not receive an instrument of succession from Dominica until 2016.

Kiribati

Following Kiribati's independence in 1979, the President of Kiribati sent a note to the UNSG stating that:
The Government of Kiribati later made statements suggesting that it did not consider itself a party to the treaty, before acceding as an independent state in 2025.

Tuvalu

Following Tuvalu's independence in 1978, the Prime Minister of Tuvalu sent a note to the UNSC stating that:
The Government of Tuvalu later made statements suggesting that it did not consider itself a party to the BWC, before acceding as an independent state in 2024.

Vanuatu

Following Vanuatu's independence in 1980, it was listed as a state party to the BWC in documents from the Meetings of the States Parties to the BWC. However the Government of Vanuatu made statements suggesting that it did not consider itself a party to the treaty, and the UK depositary did not receive an instrument of succession from Vanuatu until 2016.