Last updated: 2026-10-11 · Tax rules change. The 2026 figures use the IRS draft 2026 Schedule SE. Verify with official sources before acting.
This self-employment tax calculator follows Schedule SE (Form 1040) line by line: it takes your net profit, applies the 92.35% step, the Social Security wage base and any W-2 wages, and shows the Social Security and Medicare parts, the half you can deduct, and the 0.9% Additional Medicare Tax if it applies. Runs in your browser. Nothing is sent anywhere; your entries are remembered only in this browser.
Self-Employment Tax Calculator
Planning estimate, not tax advice. Regular method only: no farm, church employee, or optional-method income. Self-employment tax is figured per person; for married filing jointly, the 0.9% threshold applies to both spouses' combined wages and self-employment income. General partners may need to reduce the K-1 amount as the Schedule SE instructions describe. Confirm with a CPA.
Forvendo · every other Friday
One operating decision, worked through with numbers
The same approach this calculator takes: the sources named, the assumptions shown, and the arithmetic left where you can check it.
No spam, unsubscribe any time. The calculators and every download stay free whether you subscribe or not.
How this self-employment tax calculator works
It uses the regular method on Schedule SE, Part I. Each step below is a line on the form.
| Step | Schedule SE | What happens |
|---|---|---|
| 1. Net profit | Line 2 | Your Schedule C line 31, plus partnership income from Schedule K-1 (Form 1065) box 14 code A if you are a partner or multi-member LLC owner. All businesses are combined, and a loss in one reduces the profit of another |
| 2. Net earnings | Line 4a | If line 3 is more than zero, multiply it by 92.35% (0.9235) |
| 3. The $400 test | Line 4c | Under $400, the form says to stop: “you don’t owe self-employment tax.” That is about $434 of net profit |
| 4. Room under the wage base | Lines 7 to 9 | The Social Security wage base, minus Social Security wages from any W-2 (boxes 3 and 7). Not below zero |
| 5. Social Security part | Line 10 | 12.4% of the smaller of net earnings or that room |
| 6. Medicare part | Line 11 | 2.9% of all net earnings. There is no cap |
| 7. Self-employment tax | Line 12 | Lines 10 and 11 added together |
| 8. Deductible half | Line 13 | 50% of line 12, carried to Schedule 1. The IRS says it “only affects your income tax” |
The 0.9% Additional Medicare Tax is figured separately, on Form 8959. It applies to net earnings (line 6, after the 92.35% step) above a threshold, and the threshold is reduced first by your W-2 Medicare wages (box 5). It is not part of the deductible half: the tax code’s deduction for half of self-employment tax excludes it.
The 2026 and 2025 numbers
| Figure | 2025 | 2026 | Source |
|---|---|---|---|
| Social Security rate | 12.4% | 12.4% | Schedule SE line 10 |
| Medicare rate | 2.9% | 2.9% | Schedule SE line 11 |
| Net earnings factor | 92.35% | 92.35% | Schedule SE line 4a |
| Minimum net earnings to owe the tax | $400 | $400 | Schedule SE line 4c |
| Social Security wage base | $176,100 | $184,500 | SSA; Schedule SE line 7 |
| Additional Medicare Tax threshold | $250,000 married filing jointly · $125,000 married filing separately · $200,000 single, head of household, or qualifying surviving spouse. The Form 8959 instructions say these “aren’t indexed for inflation” | Form 8959 instructions | |
As of 2026-10-11, the IRS lists the 2025 Schedule SE as the current revision. The 2026 wage base of $184,500 comes from SSA and also appears on the IRS draft 2026 Schedule SE and the final 2026 Form 1040-ES. The draft’s “What’s New” lists the wage base as the only change to these figures for 2026.
Three worked examples (2026)
| Side business only | W-2 job plus side business | High earner | |
|---|---|---|---|
| Net profit | $60,000 | $100,000 | $250,000 |
| W-2 Social Security and Medicare wages | $0 | $120,000 | $0 |
| Net earnings (× 92.35%) | $55,410.00 | $92,350.00 | $230,875.00 |
| Social Security part | $6,870.84 | $7,998.00 (on $64,500 of room) | $22,878.00 (capped at $184,500) |
| Medicare part | $1,606.89 | $2,678.15 | $6,695.38 |
| Self-employment tax | $8,477.73 | $10,676.15 | $29,573.38 |
| Deductible half | $4,238.87 | $5,338.08 | $14,786.69 |
| Additional Medicare Tax (single filer) | $0 | $111.15 | $277.88 |
The middle column is the case most hand calculations get wrong. The $120,000 of W-2 wages already used most of the $184,500 wage base, so only $64,500 of the side income gets the 12.4% Social Security part. The Medicare part has no cap, and the wages also reduce the $200,000 threshold to $80,000 for the 0.9% tax.
Why there are two wage boxes
Schedule SE and Form 8959 use different W-2 figures. The wage base on Schedule SE line 8a is reduced by Social Security wages, boxes 3 and 7, from your own W-2s. The 0.9% threshold on Form 8959 is reduced by Medicare wages, box 5. For many people these are the same number, but they can differ, so the calculator asks for both, and it flags it when only one is filled in. For married filing jointly, filling in only the Medicare box can be correct when the W-2 is your spouse’s, and the calculator says so instead of warning. If you have no W-2 job, leave both blank.
Self-employment tax is figured per person. The Schedule SE instructions say that if both spouses have self-employment income, each files a separate Schedule SE, so run the calculator once for each of you. For the 0.9% tax on a joint return, Form 8959 combines both spouses’ Medicare wages and self-employment income against the $250,000 threshold. Enter your combined Medicare wages, and your spouse’s net profit in its own box, and the 0.9% line shows the combined figure for the household.
What the calculator does not cover
- Income tax. Self-employment tax is on top of income tax, and quarterly estimated payments cover both. To size those payments, use the self-employed estimated tax calculator.
- Optional methods (Schedule SE Part II), farm income, Conservation Reserve Program payments, and church employee income.
- Unreported tips and Form 8919 wages, which also reduce the wage base on lines 8b and 8c.
- The 0.9% Additional Medicare Tax on wages themselves. The calculator shows only the part on self-employment income; Form 8959 figures the wage part separately.
- State taxes.
Related
- Self-employed estimated tax calculator: the safe-harbor amount and four payment periods
- Quarterly estimated taxes for a one-person store
- 1099-K calculator: from the gross on the form to net receipts
Frequently asked questions
How is self-employment tax calculated?
Multiply net profit by 92.35% to get net earnings. If that is $400 or more, the tax is 12.4% of net earnings up to the Social Security wage base (less any W-2 Social Security wages) plus 2.9% of all net earnings. That is the 15.3% rate most people quote, applied to 92.35% of profit.
What is the self-employment tax rate for 2026?
15.3%: 12.4% for Social Security and 2.9% for Medicare. The Social Security part applies only up to the wage base, which is $184,500 for 2026 according to SSA. A 0.9% Additional Medicare Tax applies when Medicare wages and self-employment income together are above $250,000 for married filing jointly, $125,000 for married filing separately, or $200,000 for single, head of household, or qualifying surviving spouse.
Do I pay self-employment tax if I made less than $400?
If net earnings on Schedule SE line 4c are less than $400, the form says you don’t owe self-employment tax. Because net earnings are 92.35% of profit, that is about $434 of net profit. Church employee income has a separate rule.
Can I deduct self-employment tax?
Half of it. Schedule SE line 13 carries 50% of the tax to Schedule 1 as a deduction. The IRS says this deduction only affects your income tax; it does not lower the self-employment tax itself. The 0.9% Additional Medicare Tax is not included in the deduction.
Does a W-2 job lower my self-employment tax?
It can lower the Social Security part. W-2 Social Security wages use up part of the wage base, so less of your self-employment income is subject to the 12.4%. If your wages are at or above the wage base, the Social Security part is zero. The 2.9% Medicare part still applies to all net earnings.