Additional Medicare
Additional Medicare 0.9% on RSU income over $200k / $250k.
Reviewed August 21, 2026. About. Not tax advice.
Additional Medicare tax is 0.9% on wages over $200,000 (single) or $250,000 (MFJ). RSU vests are wages. On the Bay Area IC sample the extra Medicare slice of the gap is $2,250 — real money, usually dwarfed by the 22% income-tax hole ($32,500 federal). Employers generally withhold additional Medicare once the year-to-date wages they see cross the line; a second job or a spouse’s W-2 can still leave a filing-time catch-up.
On the Bay Area sample
Still due $34,925 = federal income gap $32,500 + additional Medicare $2,250 + state $175.
FAQ
- Is additional Medicare part of the 22%?
- No. 22% is federal income-tax withholding on supplemental wages. Medicare (1.45% + 0.9%) is a separate payroll tax.
- Does Social Security apply to my vest?
- Only until the annual wage base ($184,500 in the 2026 tables we use). A $285k salary has already cleared it, so extra SS on the vest is usually $0.
Sources
- IRS Publication 15 (Circular E) — Supplemental wage withholding: 22% up to $1 million, 37% above.
- IRS tax year 2026 inflation adjustments (Rev. Proc. 2025-32) — 2026 federal brackets and standard deduction.
- IRS estimated taxes — 1040-ES installment dates and underpayment penalty.