My city is asking for an S-1040 form. I can find the normal 1040 but where do I find the S-1040?

You have not mentioned your city.   We cannot see your information.    TurboTax only prepares local (city) returns for a few cities.  You might be on your own to sort this out with your city.

 

 

TurboTax only prepares a few city or local tax returns as an extra step in your state return.  For most local tax returns you are on your own.  You may have to ask around amongst your neighbors, etc. to find out if you have a local tax and how to pay it. “Google “ local tax for your area.  Call your city government, etc.  Your only record of paying your local tax will be your own bank/credit card records

 

https://ttlc.intuit.com/questions/1899325-which-city-tax-returns-can-i-do-in-the-turbotax-state-program

 

What city is asking for a S-1040?  That is not a federal form.

 

The only Form S-1040 using a Google search is for the city of Saginaw, Michigan