S-Corp Shareholder Basis Tracker · free, in your browser
Which K-1 box feeds which line of S corporation basis
Your Schedule K-1 (Form 1120-S) never states your stock basis. It gives the year's amounts, and you carry basis forward yourself. This is where each box goes.
Box by box
| K-1 box | What it is | Effect on basis |
|---|---|---|
| 1-10 | Ordinary business income, rental, interest, dividends, royalties, gains (a negative figure is a loss) | Income raises basis; a loss is limited by basis |
| 11, 12 | Section 179 and other deductions | Treated as losses |
| 16A, 16B | Tax-exempt income | Raises basis, untaxed |
| 16C | Nondeductible expenses | Lowers basis, after distributions |
| 16D | Distributions | Lowers basis; the part above basis is gain |
| 16E | Repayment of loans from shareholders | Applies to debt basis, not stock |
The K-1 does not show money you contributed or lent during the year. Add those from your own records.
One invented year
You open 2024 with $30,000 of stock basis. Box 1 shows $50,000, box 16A $2,000, box 16C $3,000 and box 16D $20,000. Basis rises by $52,000 to $82,000, the $20,000 distribution is not taxed, and the $3,000 of nondeductible expenses comes off after it, so stock basis at year end is $59,000.
In the tracker, type 2024: 1=50000, 16A=2000, 16C=3000, 16D=20000 into the K-1 box entry and it fills the year table for you.
Questions
Which K-1 box is my S corporation stock basis?
None. The K-1 does not report your basis; you track it yourself from year to year. The K-1 gives the yearly amounts that raise or lower it, and Form 7203 is where the roll-forward is shown.
Do distributions in box 16D reduce my basis?
Yes, after income and other increases are added. A distribution up to your stock basis is not taxed; the part above it is taxed as a gain. Distributions come before nondeductible expenses and losses in the order basis is adjusted.
Does tax-exempt income in box 16A raise my basis?
Yes. Tax-exempt interest and similar income passes through untaxed but still increases stock basis, so leaving it out understates your basis.
Open the tracker and put your own K-1 figures through it. Nothing is uploaded. Related: the order basis is adjusted in and why a loss is suspended.