Box 6 represents reductions/adjustments made to scholarships or grants reported in Box 6 on a prior year Form 1098-T, and may affect the amount of any allowable tuition and fees deduction or education credit you may claim for a prior year.
For example, you may have initially been awarded a $2,000 Pell grant for the spring 2019 term, and that Pell grant was disbursed to (reflected on) your student account as of December 2018. Because the award was assessed to/”paid” your account during the 2018 calendar year, it was originally included in Box 5 of your 2018 1098-T. In February 2019, however, you dropped below full-time status, and per federal regulations, Financial Aid reduced your spring 2019 Pell award to $1,000. The $1,000 reduction in your original Pell award would appear in Box 6 of your 2019 Form 1098-T because the adjustment occurred during calendar year 2019.
We encourage you to consult your tax professional, IRS Form 8863, or IRS Publication 970 for guidance in including these adjustments on your federal tax return.