Box 6. Shows certain real estate tax on a residence charged to the buyer at settlement. If you have already paid the real estate tax for the period that includes the sale date, subtract the amount in box 6 from the amount already paid to determine your deductible real estate tax. But if you have already deducted the real estate tax in a prior year, generally report this amount as income on the “Other income” line of Schedule 1 (Form 1040 or 1040-SR). For more information, see Pub. 523, Pub. 525, and Pub. 530.