| Country | Party | Political orientation | Reason defunct | 
| Australia | Workers Party | Libertarian |  | 
| Bahamas | Workers' Party |  |  | 
| Barbados | Workers Party of Barbados | Marxist | Defunct due to unpopularity | 
| Brazil | Worker's and Peasant's Bloc |  | 1937–1930. | 
| Brazil | Work's National Union |  | 1945–1948. | 
| Brazil | Nationalist Workers' Party |  | 1989. | 
| Brazil | Nationalist Brazilian Workers' Party |  | 1989–1992. Merged into Labour Party of Brazil.
 | 
| Brazil | General Workers' Party |  | 1995–2003. Merged into Liberal Party.
 | 
| Cambodia | Workers' Party of Kampuchea (1960–1966) | Communist | Renamed to Communist Party of Kampuchea in 1966. Dissolved in 1981. | 
| Canada | Workers' Party of Canada (1922–1924) | Communist | Legal face of the illegal Communist Party until the government's ban was lifted. | 
| Canada | Workers' Party of Canada (1934–1937) | Trotskyist | Dissolved upon entry into the Co-operative Commonwealth Federation. Reformed in 1939 as the Socialist Workers League. | 
| Canada | Revolutionary Workers Party (1946–1952) | Trotskyist | Entered the Co-operative Commonwealth Federation. | 
| Croatia | Croatian Workers Party (1906–1918) | Left-wing populist |  | 
| Czech Republic | Workers' Party | National Socialist | Banned in 2010 by the Supreme Administrative Court of the Czech Republic | 
| Estonia | Estonian Workers' Party | Communist |  | 
| Ethiopia | Workers' Party of Ethiopia | Marxist–Leninist | Overthrown in 1991 | 
| Finland | Socialist Workers' Party of Finland | Marxist | Banned in 1923 | 
| France | Workers' Party (France, 1991–2008) | Trotskyist |  | 
| Germany | German Workers' Party | Nationalist | Renamed the National Socialist German Workers' Party in 1920 | 
| Germany | National Socialist German Workers' Party | National Socialist | Dissolved and banned in 1945 | 
| Germany | Workers' Party of Germany | Juche |  | 
| Hungary | Hungarian Workers' Party | National Socialist | Dissolved and regrouped | 
| Ireland | Irish Workers' Party | Communist | Merged with the Communist Party of Northern Ireland to reconstitute the all-Ireland Communist Party of Ireland in 1962 | 
| Israel | Workers Party of Eretz Israel (Mapai) | Labor Zionism | Merged into the Israeli Labor Party | 
| Israel | United Workers Party (Mapam) | Labor Zionism | Merged into Meretz | 
| Israel | Workers of Agudat Yisrael | Haredi Judaism |  | 
| Korea | Workers' Party of North Korea Workers' Party of South Korea
 | Communist Communist
 | Merged to form the Workers' Party of Korea in 1949 | 
| Latvia | Workers' Party | Left-wing politics |  | 
| Mexico | Mexican Workers' Party | Social democratic | Merged with the Unified Socialist Party of Mexico to form the Mexican Socialist Party in 1987 | 
| New Zealand | Workers Party of New Zealand | Marxist | Renamed to Fightback in 2013 | 
| North Macedonia | Workers Party | Left-wing politics |  | 
| Poland | Polish Workers' Party | Communist | Merged to form the Polish United Workers' Party in 1948 | 
| Poland | Polish United Workers' Party | Marxist–Leninist | Self-dissolved in 1990 | 
| Poland | Zionist Workers Party |  | 
| Romania | Romanian Workers' Party | Communist | Renamed the Romanian Communist Party in 1965 | 
| South Africa | Workers Party of South Africa | Trotskyist | Banned in 1953 | 
| Spain | Workers' Party of Marxist Unification | Marxist | Dissolved in 1980 | 
| Trinidad and Tobago | Workers and Farmers Party | Marxist | Defunct due to unpopularity | 
| Trinidad and Tobago | British Empire Citizens' and Workers' Home Rule Party | Garveyism | Popularly known as the Butler Party, defunct due to unpopularity | 
| Trinidad and Tobago | Progressive Workers Democrat Movement |  | Defunct due to unpopularity | 
| Turkey | Workers' Party | Scientific socialist | Renamed the Patriotic Party in 2015 | 
| United Kingdom | International Leninist Workers Party | Marxist–Leninist | Dissolved into the Socialist Labour Party in 1996 | 
| United Kingdom | Workers Party of Scotland | Marxist–Leninist |  | 
| United States | Democratic Workers Party | Marxist–Leninist | Dissolved in 1986 | 
| United States | Workers Party | Trotskyist | Renamed the Independent Socialist League in 1949 | 
| United States | American Workers Party | Musteite | Merged into Workers Party of the United States | 
| United States | Workers Party of America | Marxist–Leninist | Became Communist Party USA in 1929. | 
| United States | Workers Party of the United States | Trotskyist | Absorbed into the Socialist Party of America in 1936 |