How do I know what my double-taxed (by two states) income was, and what my tax paid on double-taxed income was?

[jiachensun2002]

I am an MD resident but working in CT (filing as a non-resident). I do not know what is my "tax paid to Connecticut on double-taxed income." Is this the "state income tax" portion of my W2? Does this include box 14 (CTPL)?

[MindyB]

Since you are filing as a non-resident in Connecticut, the entirety of the Connecticut tax you are paying is on "double-taxed income." This amount can be found on Connecticut Form CT-1040NR/PY Line 16.

Connecticut will tax the work performed in the state. You will file a non-resident return for the work performed in Connecticut, then you will take a credit for taxes paid to other states on your Maryland return.  

Here's how to claim the credit for taxes paid to other states: 

1. First prepare the non-resident CT return (don't skip this step or the credit might not populate correctly)

2. Next, prepare the resident MD return.

3. TurboTax will compute the credit for taxes paid in other states.

Here is a TurboTax article you may find helpful: How do I file a nonresident state return?