Is there a place to store account numbers?

[AC Question]

I have business phone numbers in my phone but I need to have their account numbers on file as well. Is there a place to store the acct number info?

 

[cpaight]

Open the contact, hit the 3-dots button to edit it, scroll to the bottom and there's a button that says "Add new field"....there's an option to add a Notes field.