Ohio does a convoluted tax calculation for non-residents/part year residents. It calculates tax on total income, then it calculates a non resident/part year resident credit, which it subtracts from the tax it calculated on the total income. The credit is calculated as your non-Ohio income divided by Total adjusted Income multiplied by the total tax. TurboTax (TT) does this by allocating your income as either Ohio or non-Ohio. W-2 income will be allocated by the state name abbreviation shown in box 15 of your W-2*. TT will ask you, item by item, in the state section, how much of your other income is Ohio or non-Ohio income. Make sure that your non-Ohio wages show NH (Other state postal abbreviation) in box 15 of your W-2 screen, with the NH amount in box 16. Since NH does not have an income tax, boxes 15-17 may be blank on your actual W-2*.
This system allows Ohio to apply their highest tax rate, based on your total income, while only taxing your Ohio income.
Ohio has a nonresident credit allocation form.. IT NRC
*Also be advised that you may have to use a work around, if your W-2 does not show OH in box 15 for the time you were still an OH resident. At the w-2 screen split the boxes 15-20 W-2 info into 2 lines. On the 1st line put OH in box 15 and the amount of wages earned while an OH resident in box 16 and leave box 17 blank. On the 2nd line put NH in box 15 and the wages amount, since the move, in box 16; leave box 17 blank..
