I think I said I’ll mail it now, but do I have to? If so what forms do I include and what happens if they get it after the due date?
Yes, Arizona does not accept e-filed amended returns, you will need to mail it in. When you print the return and instructions for mailing, you will be given a list of what you need to include. This will generally include the forms you changed along with the form 104X.
What forms do I need to mail? It says 140x, my w2s, the 1099-misc form, anything else? What is the 104x form?
No, there is nothing else to mail with your amended Arizona (AZ) return. The Form 1099-MISC is not required to be mailed unless there is state withholding. Form 104X is the Arizona (AZ) amended return. It will be one of the forms that will print when you are completing your return.