How do I find basis in retirement plan for state taxes?

[bwisdalejrfan8]

When filing my state taxes it is asking for basis in retirement plan. I have no clue what that means or how to find it.

[ToddL]

What kind of retirement plan do you have?

[bwisdalejrfan8]

Its was a 401k. I had left my job & had to close ny 401k. When doing my state taxes its asking for the basis. I have no clue what that is or how to find it.

[ToddL]

Did you ever make any after-tax contributions to this 401K (very uncommon) or were they all made to reduce your taxable income (pre-tax, very common)?

[bwisdalejrfan8]

As far as i know they were all pre-tax

[ToddL]

If this was a traditional 401K, your "basis" in the account would have been "0".

"Basis" in a retirement plan is whatever after-tax contributions you made to that plan. When you withdraw funds from that plan, some portion of the withdrawal is a return of "basis" and that is not taxable.

Example: Assume the value of your account is $10,000 and you had made $1,000 of after-tax contributions. If you withdraw the entire amount, only $9000 is taxable income. The remaining $1000 would be a return of your basis. 

If you withdrew $1000, only $900 would be taxable. The remaining $100 would be a return of your "basis".