Additional Medicare 0.9% for Self-Employed Calculator (2026)
Self-employed individuals owe 2.9% regular Medicare + 0.9% Additional Medicare on net SE earnings above $200K single / $250K married. Unlike employees, you self-report on Form 8959 instead of having it withheld.
| SE income (multiplied by 92.35%) | — |
| Combined income (SE × 0.9235 + W-2) | — |
| Threshold | — |
| Excess over threshold | — |
| Additional Medicare 0.9% | — |
| Less already withheld | — |
| Balance owed on Form 8959 | — |
Self-employed individuals pay regular Medicare tax of 2.9% on net self-employment earnings (after the 92.35% adjustment), plus an Additional Medicare Tax of 0.9% on combined wages + SE income above the filing threshold ($200K single / $250K married). Unlike W-2 employees who have the 0.9% withheld automatically, self-employed pay through quarterly estimated taxes or owe it all on Form 8959 at filing.
How The 0.9% Stacks On SE Tax
Self-employment tax has three layers in 2026. (1) 15.3% on net SE earnings up to the Social Security wage base ($176,100 in 2026) — split as 12.4% SS + 2.9% Medicare. (2) 2.9% Medicare continues above the wage base with no cap. (3) Additional 0.9% Medicare kicks in once total combined income (wages + SE) exceeds $200K/$250K. The 0.9% is calculated on Form 8959 and reconciled against any employer-withheld additional Medicare on a spouse's or your own W-2.
Quarterly Estimates Must Cover This
The IRS expects payment as income is earned. If your annual additional Medicare exceeds $1,000 and you don't make quarterly estimated payments, you owe an underpayment penalty under Section 6654. Build the 0.9% into your quarterly Form 1040-ES calculations once you cross the threshold. Common planning move: S corp election lets owners split income between W-2 wages (subject to Medicare + additional Medicare) and shareholder distributions (no SE tax, no Medicare). IRS requires 'reasonable compensation' as W-2 — typically 30-60% of total income. The split saves the Medicare/additional Medicare on the distribution portion. Consult a CPA — the savings are real but the audit risk on under-paid salary is also real.
Last updated May 2026. Sources: IRS Form 8959.