FICA Tax Explained: Social Security, Medicare and OASDI

FICA is the federal payroll tax that funds Social Security and Medicare. In 2026 it takes 6.2% of your wages for Social Security, up to $184,500 of pay, and 1.45% of all wages for Medicare. That is 7.65% of most paychecks. Wages over $200,000 from one employer get an extra 0.9% of Medicare tax.

FICA stands for the Federal Insurance Contributions Act, the law that sets the tax. On a $60,000 salary paid every two weeks, it comes to $176.54 a paycheck: $143.08 for Social Security and $33.46 for Medicare. The paycheck calculator shows both lines for any salary.

Is FICA the same as Social Security?

Not quite. FICA is the umbrella. Social Security is one of the two taxes under it, and Medicare is the other. When a pay stub shows a single “FICA” line, it usually means both added together. When it shows two lines, they are split out.

FICA is also separate from federal income tax. Income tax withholding depends on your W-4 and goes toward your yearly tax bill. FICA is a flat percent of wages, you can’t change it with a W-4, and it does not get settled up on your return the same way. The FAQs on whether FICA is the same as Social Security and whether FICA is the same as federal income tax go further.

Is FICA the same as OASDI?

OASDI is the official name for Social Security: Old-Age, Survivors, and Disability Insurance. So OASDI is part of FICA, the 6.2% part. Medicare’s official name is Hospital Insurance, which is why some stubs say “HI” or “FICA-HI”.

Here is how the labels on pay stubs usually line up:

Pay stub label	What it is	2026 employee rate
OASDI, SS, Soc Sec, FICA-OASDI	Social Security tax	6.2% up to $184,500
MED, Medicare, FICA-HI, HI	Medicare tax	1.45% of all wages
Addl Med, MED Addl	Additional Medicare tax	0.9% over $200,000
FICA	Both Social Security and Medicare	7.65%

The FAQ on what OASDI means on your paycheck and the OASDI glossary entry cover the name.

Social Security: 6.2% up to the wage base

Social Security tax is 6.2% of wages until your pay for the calendar year reaches the wage base. For 2026 the base is $184,500, set by the Social Security Administration. Above that, Social Security stops for the rest of the year. The most anyone pays through one employer is $11,439.

Say you earn $250,000 a year, paid every two weeks, so $9,615.38 a check. Social Security takes $596.15 from each of the first 19 paychecks. By the 20th check your year-to-date pay passes $184,500, so only $112.08 comes out. From check 21 on, Social Security is zero, and your take-home pay jumps.

It starts again on the first paycheck in January. If you earn over the wage base, that is one reason your first check of the year looks smaller than December’s. The guide on why your paycheck went down has more on that.

Medicare: 1.45% with no cap

Medicare tax is 1.45% of every dollar of wages. There is no wage base, so it never stops during the year.

On top of that, the Additional Medicare tax adds 0.9% to wages over $200,000. Employers must start withholding it on the paycheck where your pay from them that year passes $200,000, no matter your filing status or what your spouse earns. In the $250,000 example, check 21 brings year-to-date pay to $201,923.08, so $17.31 of Additional Medicare comes out. Every check after that has $86.54.

The tax you actually owe on your return can differ from what was withheld, because the real threshold depends on your filing status and your household’s combined wages. IRS Topic 560 explains how that is squared up when you file.

What counts as FICA wages

FICA applies to almost all pay: salary, hourly wages, overtime, bonuses, commissions and reported tips. Some deductions reduce it and some don’t:

Deduction	Lowers FICA wages?	Lowers federal income tax wages?
Traditional 401(k)	No	Yes
Health, dental, vision premiums (cafeteria plan)	Yes	Yes
HSA through payroll	Yes	Yes
Health or dependent care FSA	Yes	Yes
Roth 401(k)	No	No

That is why a 401(k) lowers your federal withholding but leaves the Social Security and Medicare lines alone. With $100 a check of health premiums on the $60,000 salary, FICA wages fall to $2,207.69, Social Security drops to $136.88 and Medicare to $32.01.

The no-tax-on-tips and overtime deductions also leave FICA alone. Tips and overtime are still fully taxed for Social Security and Medicare. The tips and overtime guide covers what does change.

FICA by salary in 2026

Salary	Social Security	Medicare	Total FICA	Share of pay
$40,000	$2,480	$580	$3,060	7.65%
$60,000	$3,720	$870	$4,590	7.65%
$100,000	$6,200	$1,450	$7,650	7.65%
$150,000	$9,300	$2,175	$11,475	7.65%
$200,000	$11,439	$2,900	$14,339	7.17%

These are yearly employee amounts for one job with no pre-tax health or HSA deductions. Above the wage base, the share of pay falls because Social Security has stopped.

Two jobs and the wage base

Each employer withholds Social Security up to the wage base on its own, with no idea what your other job paid. If two jobs together pay you more than $184,500, too much Social Security gets withheld. You don’t lose it: the extra counts as a credit on your federal return.

Additional Medicare works the other way. Each employer only starts withholding past $200,000 of its own pay, so two jobs at $150,000 each would have none withheld, even though you may owe it. A larger W-4 Step 4(c) amount can cover the gap.

Where to check the numbers

IRS Topic 751 lists the current Social Security and Medicare withholding rates. The glossary entry for FICA has a short definition, and the methodology page shows the exact formula the calculator uses. For how FICA fits into a full paycheck, read how to calculate take-home pay.