You can synchronise your address book with all programs or devices that support CardDAV standard.

To sync, you will generally need the following details:

• Server: posteo.de
• Port: 8843
• Encryption: SSL (compulsory)
• Username: Your Posteo address
• Password: Your Posteo password

Tip: As an alternative to using your complete Posteo address, you can also use just the first part of the address up to the @ symbol as the username.

Some programs ask for a URL (instead of specifying the server):
https://posteo.de:8843/addressbooks/john.example/default

(change john.example to your own address up to the @ symbol, make sure to use lower case throughout)

In our help pages you can find setup instructions for the following devices:

• iPhone/iPad/iPod
• Android (only possible with a paid app from a third-party provider)
• Thunderbird
• Contacts (in macOS)
• eM Client
• Outlook (only possible with a paid app from a third-party provider)

For Blackberry OS, Outlook Express, Windows Live Mail, Windows Phone 7 and 8, Windows 8, Symbian and WebOS, we do not currently know of any working support for the CardDAV standard. Please contact the relevant manufacturer and let them know if you are not satisfied with this.

Address book groups

Address book groups in the webmail interface can not yet be synchronised with the help of CardDAV. You could, however, separately create your address book groups on a device that supports CardDAV and assign the contacts to the group a second time.