What Does Box 12 Code L Mean on a W-2?
Substantiated employee business expense reimbursements. 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 L is substantiated employee business expense reimbursements.
What Code L means
Reimbursements your employer paid for business expenses you documented, at or below the federal rate.
Does Code L affect my taxes?
The substantiated portion is not taxable and is not in box 1. Anything above the allowed rate would already be in your taxable wages.
What to do about it
Nothing for the substantiated amount. Keep your records in case the reimbursement is ever questioned.
Where to find Code L 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 L. 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.