How do I file and pay unincorporated business tax (UBT) in New York City with Turbotax? Is it part of my e-file and e-payment, or I have to mail it in separately?

 If you entered the Unincorporated Business Conducted in New York Tax information in TurboTax, it will create the NYC-202 and file it with your New York state tax return. 

You must file an Unincorporated Business Tax return if you operate your business entirely or partly within New York City and your business's gross income, before any deduction for cost of goods sold or services performed, exceeds $95,000.

In TurboTax section of the New York State return, look for "Take a Look at New York Credit and Taxes" under NYC and Metro Commuter Taxes.