I am curious about amending some state taxes from previous years. How far back can I go and by when does this need to be completed?

[kerriP · Accepted solution]

Federal and I believe all states allow you to amend tax returns for three years from the date you filed your original return (or the due date if later) or two years of when you paid the tax.  

 What that means to most people  is to amend a a 2014 tax return -the due date was 04/15/15 + 3 years  would be 04/15/18.

So 2014 returns need to be amended before April 15, 2018.  It is past the time for amending 2013 returns.  

I can not say all states follow the Federal policy for amending, but I believe they do.