The 2028 Social Security tax limit is projected at roughly $198,900 under the Social Security Administration’s intermediate-cost estimate, up from the confirmed 2026 wage base of $184,500. That means earnings above about $198,900 would not be subject to the 6.2% Social Security payroll tax in 2028. The figure isn’t official yet. The SSA locks in each year’s wage base in October of the preceding year, so the final 2028 number will be announced in October 2027.
How Firm Is the $198,900 Projection
The $198,900 figure sits in the middle of a range. The SSA’s low-cost estimate, which assumes faster wage growth, puts the 2028 base as high as $203,700. The high-cost estimate, assuming slower wage growth, comes in around $190,200. The intermediate projection is the one most commonly used for planning, but the actual figure depends on wage growth over the next two years.
For context, the intermediate projection for 2027 is $190,800. Recent history shows steady increases of roughly 4.4% to 4.8% per year, driven by post-pandemic wage growth.1Social Security Administration. Contribution and Benefit Base
Why the Number Moves and Who Sets It
The wage base adjusts automatically under Section 230 of the Social Security Act. The formula multiplies a statutory base amount of $60,600 by the ratio of the most recent National Average Wage Index to the 1992 index, then rounds to the nearest $300.2Social Security Administration. 42 U.S.C. 430 – Adjustment of the Contribution and Benefit Base The most recently published index (for 2024) was $69,846.57.3Social Security Administration. National Average Wage Index
Because each year’s cap depends on wage data that lags by about two years, the SSA can’t finalize the 2028 base until late October 2027.4Social Security Administration. Cost-of-Living Adjustment (COLA) Information Congress plays no role in the annual adjustment.
What the Maximum 2028 Social Security Tax Would Be
The Social Security tax rate is set by statute at 6.2% for employees and 6.2% for employers, and it isn’t projected to change.5Office of the Law Revision Counsel. 26 U.S.C. 3101 – Rate of Tax6Office of the Law Revision Counsel. 26 U.S.C. 3111 – Rate of Tax Self-employed workers owe the full 12.4% themselves.7Office of the Law Revision Counsel. 26 U.S.C. 1401 – Rate of Tax
Applying those rates to the $198,900 projection:
- Employee maximum: $198,900 × 6.2% = $12,331.80
- Employer match: another $12,331.80
- Self-employed maximum: $198,900 × 12.4% = $24,663.60
The confirmed 2026 maximum employee contribution is $11,439.00.1Social Security Administration. Contribution and Benefit Base If the projection holds, employees earning above both caps would pay about $893 more in 2028 than in 2026, and self-employed workers about $1,786 more.
Self-employed workers can deduct the employer-equivalent half of their self-employment tax when calculating adjusted gross income on Form 1040. That deduction lowers income tax but does not reduce the self-employment tax itself.8Internal Revenue Service. Self-Employment Tax (Social Security and Medicare Taxes)
The Cap Applies Only to Social Security Tax, Not Medicare
The wage base limits Social Security tax alone. Medicare tax has no cap. Every dollar of wages is subject to the 1.45% Medicare tax, with a matching 1.45% from the employer and 2.9% total for self-employed workers.9Internal Revenue Service. Topic No. 751, Social Security and Medicare Withholding Rates A worker earning $400,000 in 2028 would pay Social Security tax on the first $198,900 (if the projection holds) and Medicare tax on the full $400,000.
A separate 0.9% Additional Medicare Tax applies to wages above $200,000 for single filers, $250,000 for married filing jointly, and $125,000 for married filing separately. Employers must begin withholding it once year-to-date wages pass $200,000, regardless of filing status.10Internal Revenue Service. Topic No. 560, Additional Medicare Tax It is not part of the Social Security tax limit, but it often hits the same paychecks.
What Happens Mid-Year When You Hit the Cap
Once your year-to-date earnings cross the wage base with a single employer, that employer stops withholding Social Security tax for the rest of the calendar year. If you reach $198,900 in September, your paychecks from October through December will be larger by 6.2% of gross wages. Medicare withholding continues. The clock resets to zero on January 1.
If You Work for More Than One Employer
Each employer withholds Social Security tax independently up to the wage base, because none of them can see what the others are paying you. If your combined wages across employers exceed the cap, more Social Security tax comes out of your paychecks than you actually owe. You recover the excess as a credit on your federal income tax return.11Internal Revenue Service. Topic No. 608, Excess Social Security and RRTA Tax Withheld
On a joint return, the credit is calculated separately for each spouse. If a single employer withheld too much by mistake, the credit route doesn’t apply: ask that employer for a corrected refund, and if they won’t fix it, file Form 843 to request the refund directly from the IRS.11Internal Revenue Service. Topic No. 608, Excess Social Security and RRTA Tax Withheld