| Åland | Åland Post |
| Albania | Posta Shqiptare |
| Andorra – French Andorra | La Poste Groupe |
| Andorra – Spanish Andorra | Correos |
| Armenia | HayPost |
| Austria | Österreichische Post |
| Azerbaijan | Azərpoçt |
| Belgium | bpost |
| Bosnia and Herzegovina | BH Pošta Sarajevo |
| Bosnia and Herzegovina | Hrvatska pošta Mostar |
| Bosnia and Herzegovina | Pošte Srpske Banja Luka |
| Bulgaria | Bulgarian Post |
| Croatia | Hrvatska pošta |
| Cyprus | Cyprus Post |
| Czechia | Česká pošta |
| Denmark | PostNord Danmark |
| Estonia | Eesti Post/Omniva |
| Faroe Islands | Postverk Føroya |
| Finland | Posti |
| France | La Poste Groupe |
| Georgia | Georgian Post |
| Germany | Deutsche Post |
| Gibraltar | Gibraltar Philatelic Bureau |
| Greece | ELTA (Hellenic Post) |
| Greenland | Tusass |
| Guernsey | Guernsey Post |
| Hungary | Magyar Posta |
| Iceland | ĺslandspóstur |
| Ireland | An Post |
| Isle of Man | Isle of Man Post Office |
| Italy | Poste Italiane |
| Jersey | Jersey Post |
| Kazakhstan | Kazpost |
| Latvia | Latvijas Pasts |
| Liechtenstein | Liechtensteinische Post |
| Lithuania | Lietuvos paštas |
| Luxembourg | POST Luxembourg |
| Malta | MaltaPost |
| Moldova | Poșta Moldovei |
| Monaco | La Poste de Monaco |
| Montenegro | Pošta Crne Gore |
| Netherlands | PostNL |
| North Macedonia | Poshta na Severna Makedoniјa |
| Norway | Posten Bring |
| Poland | Poczta Polska |
| Portugal | CTT Correios de Portugal |
| Portugal - Madeira | CTT Correios de Portugal |
| Portugal - Azores | CTT Correios de Portugal |
| Romania | Poşta Română - Romfilatelia S.A. |
| San Marino | Poste San Marino |
| Serbia | PE Post of Serbia |
| Slovakia | Slovenská pošta |
| Slovenia | Pošta Slovenije |
| Spain | Correos |
| Sweden | PostNord Sverige |
| Switzerland | Swiss Post |
| Türkiye | PTT Turkish Post |
| Ukraine | Ukrposhta |
| United Kingdom | Royal Mail |
| Vatican | Poste Vaticane |
