A CA resident friend has no filed for last 4 year. Are the calculated and itemized 2013,2014,2015,2016 CA state taxes fianlly paid in 2017 ALL deductible only in 2017?

[Rainman12 · Accepted solution]

Yes, taxes can only be deducted in year paid, regardless of what year the taxes were for.

[VolvoGirl]

And just the tax paid is deductible on the federal return.  Not any interest or penalties.  And only if you itemize deductions.

[SweetieJean]

Just be aware that Congress is considering major tax law changes for 2017, so that may change.