@BobX11 The question you are asked about your AGI refers to your federal AGI on the tax return you filed in the previous tax year. If you filed a joint return then the AGI is the same for both spouses. The IRS then matches up the AGI with the SSN's of the taxpayers who filed using those same SSN's the previous year to verify that the same person is using the same SSN on the current return---it is a fraud prevention measure. But the very backlogged IRS did not get everyone's 2019 AGI into the database so even if you used the correct AGI from line 8b of your 2019 return, the return could be rejected. So---using zero can often work and allow you to e-file.
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**
