| Austria |
Reformed Church in Austria |
| Belgium |
United Protestant Church of Belgium |
| Bulgaria |
Union of Evangelical Congregational Churches in Bulgaria |
| Croatia |
Reformed Christian Church in Croatia |
| Czech Republic |
Evangelical Church of Czech Brethren / Evangelische Kirche der Böhmischen Brüder |
| Denmark |
Reformed Synod of Denmark |
| France |
Reformed Church of France |
| France |
Reformed Church of Alsace and Lorraine |
| France |
Malagazy Protestant Church in France |
| Germany |
Church of Lippe |
| Germany |
Evangelical Reformed Church |
| Germany |
Reformed Alliance in Germany |
| Greece |
Greek Evangelical Church |
| Hungary |
Reformed Church in Hungary |
| Italy |
Waldensian Evangelical Church (Union of Waldensian and Methodist Churches) |
| Latvia |
Reformed Church in Latvia |
| Lithuania |
Synod of the Evangelical Reformed Church - Unitas Lithuaniae |
| Luxembourg |
Protestant Reformed Church of Luxemburg H.B. |
| Netherlands |
Remonstrant Brotherhood |
| Netherlands |
(former: Gereformeerde Kerken in Nederland) The Protestant Church in the Netherlands |
| Netherlands |
(former: Nederlandse Hervormde Kerk) The Protestant Church in the Netherlands |
| Poland |
Evangelical Reformed Church in Poland |
| Portugal |
Evangelical Presbyterian Church of Portugal |
| Romania |
Reformed Church in Romania - Transylvanian District |
| Romania |
Reformed Church in Romania (Oradea) |
| Serbia and Montenegro |
Reformed Christian Church in Serbia and Montenegro |
| Slovakia |
Reformed Christian Church in Slovakia |
| Slovenia |
Reformed Church in Slovenia |
| Spain |
Spanish Evangelical Church |
| Sweden |
The Mission Covenant Church of Sweden |
| Switzerland |
Federation of Swiss Protestant Churches, Fédération des Eglises protestantes de Suisse, Federazione delle Chiese evangeliche della Svizzera |
| Ukraine |
Reformed Church in Sub-Carpathia/ Reformed Church in Transcarpathia |
| United Kingdom of Great Britain and Northern Ireland |
Presbyterian Church of Wales |
| United Kingdom of Great Britain and Northern Ireland |
Union of Welsh Independents |
| United Kingdom of Great Britain and Northern Ireland |
United Free Church of Scotland |
| United Kingdom of Great Britain and Northern Ireland |
United Reformed Church |
| United Kingdom of Great Britain and Northern Ireland |
The Presbyterian Church in Ireland |
| United Kingdom of Great Britain and Northern Ireland |
Church of Scotland |
