How to add phone numbers to Skype for Business Online users

You can add a user’s telephone number through the Microsoft Office 365 portal or in the on-premises Active Directory Domain Services (AD DS), if the Directory Synchronization Tool is configured. After 24 hours, the change will be visible in the Microsoft Lync contact card for the user.

If you're using Directory Synchronization together with an on-premises AD DS, populate the telephoneNumber attribute, and let the attribute sync to Microsoft Office 365.

The telephone number must be entered by using the E.164 (international phone numbers) format. When adding international phone numbers, type the + sign, then the country code followed by the local number.

See the examples below, or search for your own country code.

Recipient's country/region Country/ code Local phone number International phone number for Lync
China 86 (12) 3456789 +86123456789
France 33 01 02 03 04 05 +330102030405
United Kingdom 44 12345 678 910 +4412345678910
United States 1 (555) 555-0155 +15555550155
Venezuela 58 414 123-1234 +584141231234

To enter an extension or access code to the number, enter the number in international format, beginning with a plus sign, add a space at the end of the phone number, enter an X (for extension), and then enter the extension number. The entered number should be like +584141231234 X1234.