Hello, I did not file state taxes for 2017. I did file federal taxes, but not the state taxes for California. How can I amend my state taxes for 2017? Thank you!

[TomD8]

See this FAQ:  https://ttlc.intuit.com/questions/4252298-how-do-i-amend-a-2017-return-in-turbotax

[VolvoGirl]

If you did not file a CA return then you do NOT amend.  You just file the original return.  How to finish a prior year,
https://ttlc.intuit.com/replies/4186197

[TomD8]

Except that filing the 2017 CA return may well cause a need to amend the taxpayer's federal return, if the taxpayer itemizes and deducts state income taxes.  Particularly since the deduction for state income taxes was not limited in 2017, as it was on 2018 returns.

[VolvoGirl]

Sorry not following you.  

[TomD8]

If the taxpayer could have deducted state income tax on his 2017 federal return but did not do so (because of not doing his state return), then after doing his CA return he may well want to amend his federal return so as include that deduction.

[VolvoGirl]

He can't deduct state taxes paid on a 2017 state tax return on a 2017 federal return.  He would have known all the deductible state taxes when he did federal the first time.  Anything paid on 2017 state return (in 2018) would go on his 2018 federal return.  Oh, do you mean to amend his 2018 federal?  But If he does his 2017 state return now in 2019 it will go on next year's 2019 federal return. Unless I haven't had my coffee yet today.

[TomD8]

"He would have known all the deductible state taxes when he did federal the first time."
That's true, if he was a W-2 employee and entered his 2017 W-2 properly including Boxes 15-19, and if he properly entered any estimated state tax payments or other state tax payments made during 2017.  Maybe it's me that needs that coffee.