What Does Box 12 Code TT Mean on a W-2?
Qualified overtime compensation. What it means, whether it is taxable, and what to do with it.
By the Easy Guides Editorial Team · Updated for 2026
Box 12 Code TT is qualified overtime compensation.
What Code TT means
The overtime premium you earned under the Fair Labor Standards Act. It is the extra half of time and a half, not your whole overtime paycheck.
Does Code TT affect my taxes?
Here is the part people get wrong: this money is already included in your box 1 wages and it is not removed from them. Code TT simply flags how much of your pay was qualifying overtime, so the no tax on overtime deduction can be calculated on your return.
What to do about it
Compare it against your pay stubs. Because it drives a deduction, an error here costs you money, so raise it with payroll before filing rather than after.
Where to find Code TT on your W-2
Look at box 12, in the middle-right of the form. It has up to four lines, labelled 12a, 12b, 12c and 12d. Those letters are only line labels. The code you want is the small letter or pair of letters printed next to the amount, and it will read TT. If you have more than four entries, your employer issues a second W-2 to carry the rest.
Not the code you were looking for? The full box 12 code list covers every letter, and the W-2 box decoder explains every box on the form.