Do I have to file a 2018 GA state tax return, as I have a W2 from employer for add'l payment on stock options in 2017 (paid in 2018)? the W2 correctly shows CO address.

[DanielV01 · Accepted solution]

If GA tax was withheld, you will file a GA nonresident return, even if the income is not taxed in GA.  But this income probably is taxed there.  For instance, if it was derived from NQSO proceeds, Georgia will consider this income to be Georgia sourced because it is compensation received from work you performed in Georgia.  

Since you are now living in CO, Colorado will tax the income also but give you a credit for the tax you pay to Georgia on that income.