This article describes two methods to add an extension number to a contact's phone number on an Android phone so that it will be automatically dialed.
How to Choose an Extension on Android
There are two ways to add extension numbers to contacts. If you can enter the extension number as soon as the call is answered, use the Pause method. If you have to wait for an automated message to finish, use the Wait method.
Once you are familiar with a contact's business phone system, you will know how to properly add the extension.
Use the Pause method to add extension numbers to a contact's phone number. The extension number can then be entered once the call is answered.
