If you are a Maryland resident and you paid income tax to another state, you may be eligible for a credit on your Maryland return. Nonresidents (filing Form 505 or Form 515) are not eligible for this credit.
A completed, signed copy of the income tax return filed in the other state must also be attached to Form 502. CAUTION: Do not use the income or withholding tax reported on the wage and tax statement (W-2 form) issued by your employer for the credit computation. Use the taxable income and the income tax calculated on the return you filed with the other state.
If you are claiming credit for taxes paid to more than one state, a separate Form 502CR must be completed for each state. Total the amount from each Form. Using only one summary section, record the total. Credit cannot be allowed for the local portion of the tax calculated on the return of the other state or on the Maryland return.