View an Extension Number of a Phone Number

Hello, Pat1061. Thank you for posting your question to the Apple Support Communities. We understand your situation and how you are looking to automatically add extensions to phone numbers that you dial with your iPhone. We’re happy to explain the available options that your device includes for this. 

With the iOS Contacts app, you can automate the dialing of an extension when the phone number requires it. To accomplish this, you’ll want to edit the contact’s phone number according to the directions listed in the following Apple Support article: 

Use Contacts from the Phone app on iPhone - Apple Support

After you open the article above, please see the section at the bottom titled: “Automate dialing an extension or passcode”. 

We hope that this information allows you to easily dial those phone numbers that require an extension. Please let us know if we can help answer any other questions. 

Cheers!