Do boxes 5a to 5l add up to box 1a?
Type the thirteen amounts from the form. The page adds the monthly boxes and compares the total with box 1a.
What the result points to
| Result | What it points to | Next step |
|---|---|---|
| The boxes add up to box 1a | The amounts were typed as printed. | Compare each month with its statement in the tie-out tool. |
| The difference equals one box | That box was left out or typed twice. | Re-read that box on the form. |
| The difference is a multiple of 9 cents | Two digits swapped in one amount. Swapping two digits changes a number by a multiple of 9. | Re-read each amount, digit by digit. |
| Anything else | A typing slip in more than one box, or a form whose boxes do not add up. | Check the thirteen amounts again, then ask the filer named on the form. |
The second and third rows are arithmetic, not a finding about your form.
Why they should add up
The IRS instructions describe box 1a as "the gross amount of the total reportable payment card/third party network transactions for the calendar year" and boxes 5a to 5l as "the gross amount of the total reportable payment transactions for each month of the calendar year". Twelve months of the same measure make the year.
Run a site for sellers or a bookkeeping practice? You can put this checker on your own page for free.
Sources, read 10 November 2026: IRS, Instructions for Form 1099-K (revision 12/2026 as shown on the page).
Check your own form. Drop your statement CSVs and type the box amounts. Read in your browser, nothing uploaded.
Open the tie-out toolQuestions
Should boxes 5a to 5l add up to box 1a?
The IRS instructions describe box 1a as the gross amount for the calendar year and boxes 5a to 5l as the gross amount for each month of that year. Twelve months of the same measure add up to the year.
Which month is box 5g?
July. Box 5a is January and box 5l is December, in order.
Does this check my statements?
No. This page only adds the thirteen amounts you type. To compare each month with a statement CSV, use the tie-out tool on the home page.