table markdown
| Country/Territory/Observer | Postal operator |
| Antigua and Barbuda | Antigua and Barbuda Postal Service |
| Argentina | Correo Oficial de la República Argentina S.A. |
| Aruba | Post Aruba N.V. |
| Australia | Australia Post |
| Austria | Österreichische Post AG |
| Azerbaijan | Azerpost LLC |
| Barbados | Barbados Postal Service |
| Belgium | bpost |
| Country/Territory/Observer | Postal operator |
|---|---|
| Antigua and Barbuda | Antigua and Barbuda Postal Service |
| Argentina | Correo Oficial de la República Argentina S.A. |
| Aruba | Post Aruba N.V. |
| Australia | Australia Post |
| Austria | Österreichische Post AG |
| Azerbaijan | Azerpost LLC |
| Barbados | Barbados Postal Service |
| Belgium | bpost |
::: spoiler Title
| Country/Territory/Observer | Postal operator |
|---|---|
| Antigua and Barbuda | Antigua and Barbuda Postal Service |
| Argentina | Correo Oficial de la República Argentina S.A. |
| Aruba | Post Aruba N.V. |
| Australia | Australia Post |
| Austria | Österreichische Post AG |
| Azerbaijan | Azerpost LLC |
| Barbados | Barbados Postal Service |
| Belgium | bpost |
:::