Payroll Guide

What Is FICA Tax? (2025)

FICA tax explained: what the Federal Insurance Contributions Act covers, how Social Security and Medicare withholding is calculated, what employers pay separately, and why FICA and federal income tax withholding are not the same thing. Based on 2025 IRS Publication 15 rates.

Direct Answer

FICA tax is the Federal Insurance Contributions Act tax. It funds Social Security and Medicare. For 2025, employees pay 6.2% for Social Security on wages up to $176,100 and 1.45% for Medicare on all wages with no cap. Employers match both rates separately. FICA appears as two distinct line items on every W-2 paycheck and is not the same as federal income tax withholding.

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Written by Munib Ur Rehman  ·  Reviewed by Nausheen Shahid (LMN Tax Inc.)  ·  Tax Year 2025
Key Takeaways
  • FICA stands for Federal Insurance Contributions Act. It covers Social Security tax and Medicare tax — not federal income tax withholding.
  • For 2025, the Social Security rate is 6.2% on wages up to $176,100. The Medicare rate is 1.45% on all wages with no ceiling.
  • Employers match both FICA rates dollar for dollar. That employer match does not appear on the employee's pay stub.
  • Employees earning more than $200,000 in a year pay an additional 0.9% Medicare surtax on wages above that amount. Employers do not match this surtax.
  • Social Security withholding stops for the calendar year once cumulative wages from one employer reach $176,100. Medicare withholding never stops.

What Does FICA Stand For?

FICA stands for Federal Insurance Contributions Act. It is the federal law that requires both employees and employers to contribute to Social Security and Medicare through mandatory payroll withholding.

The act was originally established to fund the Social Security program in 1935. Medicare was added in 1965. The contributions fund two separate federal programs: Old-Age, Survivors, and Disability Insurance (OASDI, commonly called Social Security) and Hospital Insurance (HI, commonly called Medicare).

When someone refers to "FICA tax," they mean the combined withholding for both programs. The two components always appear separately on a pay stub.

What Does FICA Tax Include?

FICA tax has two components, each governed by a separate rate and separate rules. Both apply to most W-2 employees in covered employment.

ComponentWho PaysRate (2025)Wage Cap
Social Security TaxEmployee + Employer (each)6.2%$176,100
Medicare TaxEmployee + Employer (each)1.45%None
Additional Medicare TaxEmployee only (no employer match)0.9%Wages over $200,000 ($250,000 MFJ)

Social Security Tax

For 2025, Social Security tax is 6.2% on covered wages up to $176,100. This ceiling is called the Social Security wage base. Once an employee's cumulative wages from one employer reach $176,100 in a calendar year, Social Security withholding stops for the rest of that year. The wage base is adjusted annually by the Social Security Administration based on wage growth.

Both the employee and the employer each pay 6.2%. The employee's share is withheld from gross wages. The employer's share is paid separately and does not reduce the employee's gross pay.

Medicare Tax

Medicare tax is 1.45% on all covered wages with no wage base cap. It applies to every dollar of earnings throughout the calendar year. There is no ceiling.

Like Social Security, the employer matches the 1.45% rate separately. Neither the employee nor the employer can waive or reduce this rate through elections or withholding adjustments.

Additional Medicare Tax

The Additional Medicare Tax is 0.9% on wages above $200,000 for single filers and $250,000 for married filing jointly. It is an employee-only tax. The employer does not match it.

Employers are required to begin withholding the Additional Medicare Tax once an employee's wages from that employer exceed $200,000 in a calendar year, regardless of the employee's filing status. If the employee's actual threshold is different (for example, $250,000 for a married couple), any over- or under-withholding is reconciled on Form 1040 at year-end.

Is FICA the Same as Federal Income Tax Withholding?

No. This is the most common point of confusion about paycheck deductions. FICA and federal income tax withholding are two separate taxes that both appear as deductions on a pay stub.

FeatureFICA TaxFederal Income Tax Withholding
What it fundsSocial Security and Medicare programsGeneral federal government operations
RateFixed by law (6.2% SS + 1.45% Medicare)Variable — depends on W-4, income, filing status
Employer obligationEmployer matches employee FICA ratesEmployer withholds on behalf of employee only
Affected by W-4?NoYes
Wage base limit?Yes (SS only, $176,100 for 2025)No
How reconciledGenerally final — no year-end refund of FICAReconciled on Form 1040; refund or balance due

The key distinction is this: FICA rates are fixed by statute. Changing your Form W-4 has no effect on Social Security or Medicare withholding. Federal income tax withholding is an estimate that varies based on your elections, income level, and pay frequency.

Both are remitted to the IRS. But they fund different programs, are calculated under different rules, and serve different purposes.

How Is FICA Calculated on a Paycheck?

FICA is calculated on gross wages before pre-tax deductions reduce the income tax withholding base. This distinction matters. A 401(k) contribution reduces the wages subject to federal income tax. It does not reduce the FICA base.

Social Security Calculation

Multiply gross wages by 6.2%, until cumulative year-to-date wages from that employer reach $176,100 (2025). After that threshold, Social Security withholding is zero for the remainder of the calendar year.

Medicare Calculation

Multiply gross wages by 1.45%. No ceiling applies. This calculation runs on every paycheck for the entire year.

Additional Medicare Tax Calculation

Once cumulative wages from a single employer exceed $200,000, the employer begins withholding an additional 0.9% on the excess. The employer does not match this rate. If the employee's actual filing-status threshold is higher (for example, $250,000 for married filing jointly), the excess withholding is refunded on Form 1040.

Employer Matching

Employers remit their own matching contributions of 6.2% (Social Security) and 1.45% (Medicare) entirely from employer funds. These amounts do not come out of the employee's wages and are not visible on the pay stub. They represent a separate payroll cost on top of gross wages.

Why Does FICA Appear on Your Pay Stub?

Every W-2 employee in covered employment sees FICA deductions on each paycheck. The two components typically appear under labels such as "Social Security Tax," "OASDI," "Fed OASDI/EE," "Medicare Tax," or "Fed MED/EE," depending on the payroll system used by the employer.

These two deductions reduce gross pay to arrive at taxable wages for income tax purposes. But because FICA is calculated on gross wages, not on taxable wages, pre-tax deductions do not reduce FICA. A $400 biweekly 401(k) contribution reduces federal income tax withholding but has no effect on the $153 in combined Social Security and Medicare owed on a $2,000 paycheck.

Paycheck calculators estimate FICA by applying these rates to your gross wages. The hourly paycheck calculator and the salary paycheck calculator both apply the 2025 Social Security wage base and Additional Medicare Tax threshold to produce a complete withholding breakdown.

See Your FICA Withholding by Paycheck

Enter your hourly rate or annual salary to see a full 2025 paycheck breakdown including Social Security, Medicare, and federal income tax withholding.

Hourly Calculator Salary Calculator

Real-World Examples: FICA on Three Different Paychecks

These examples use 2025 IRS rates. All figures are per pay period unless noted.

Example 1 — Standard Employee

Maria, $52,000/year, biweekly, Texas (no state income tax)

Gross pay per period: $52,000 ÷ 26 = $2,000.00

  • Social Security (6.2% × $2,000): $124.00
  • Medicare (1.45% × $2,000): $29.00
  • Total FICA per period: $153.00
  • Annual FICA (employee share): $3,978.00 ($3,224 SS + $754 Medicare)

Maria's employer simultaneously remits $124 in Social Security and $29 in Medicare per period on top of her wages. She does not see this on her pay stub. Social Security withholding continues for all 26 pay periods because $52,000 is well below the $176,100 wage base.

Example 2 — High-Earner Wage Base Impact

Carlos, $220,000/year, biweekly, single filer

Gross pay per period: $220,000 ÷ 26 = $8,461.54

Social Security wage base of $176,100 is reached around period 21 ($176,100 ÷ $8,461.54 = ~20.8 periods). After that point, Social Security withholding stops for the year. Carlos's final paychecks show higher net pay because the $524.62 Social Security deduction disappears.

Additional Medicare Tax: Carlos's wages exceed $200,000. His employer begins withholding 0.9% on the excess once cumulative wages pass $200,000 (around period 23.6). The surtax applies to approximately $20,000 in excess wages, adding $180.00 in total employee-side Additional Medicare Tax for the year.

  • Annual FICA (employee share): $10,918.20 (SS on $176,100) + $3,190.00 (Medicare on $220,000) + $180.00 (Addl Medicare on $20,000) = $14,288.20
Example 3 — FICA vs Federal Withholding Side by Side

Same paycheck, two different deduction types

On a $2,000 gross paycheck for a single employee earning $52,000/year with no pre-tax deductions:

  • Social Security withholding (FICA): $124.00 — same regardless of W-4
  • Medicare withholding (FICA): $29.00 — same regardless of W-4
  • Federal income tax withholding: approximately $162.00 — varies by W-4 elections and filing status

If that same employee adds $500 per paycheck in W-4 Step 4(c) extra withholding, the federal income tax withholding rises to approximately $662.00. The FICA withholding stays at $153.00. Nothing in the W-4 can change FICA.

How FICA Connects to the Payroll Tools

Understanding FICA rates is useful. Seeing the actual dollar amounts for your specific wages and pay schedule is more useful.

The hourly paycheck calculator applies the 2025 FICA rates to your hourly wage and hours worked. It shows the exact Social Security and Medicare amounts per pay period, accounts for the $176,100 Social Security wage base, and handles the Additional Medicare Tax threshold. The output is a full per-period deduction breakdown including federal income tax withholding.

The salary paycheck calculator does the same for annual salaried workers across weekly, biweekly, semimonthly, and monthly pay frequencies. Enter your salary and W-4 filing status. The calculator shows FICA, federal withholding, and estimated net pay per period.

Once you have a paycheck in hand, the pay stub guide explains every line item, including how to identify FICA, verify the amounts match your wage rate, and understand why YTD figures differ from per-period amounts.

For a complete explanation of all withholding components and how they interact, see the how payroll taxes work guide, which covers the full gross-to-net deduction sequence, employer costs, and W-4 impact.

Common Misunderstandings About FICA

FICA Means All Payroll Taxes

FICA refers specifically to Social Security and Medicare. In everyday usage, people often say "payroll taxes" to mean all withholding from a paycheck, including federal income tax. Technically, federal income tax withholding is not a FICA tax. It is a separate statutory obligation governed by IRC sections 3401 through 3404.

Updating Your W-4 Reduces FICA

It does not. FICA rates are fixed by law. No W-4 election changes them. Claiming additional dependents on Step 3 of the W-4 reduces federal income tax withholding only. Social Security and Medicare withholding remain exactly the same.

Social Security Withholding Stops for Everyone at the Same Time

The Social Security wage base is a cumulative per-employer threshold, not a calendar date. A worker earning $60,000 per year never reaches $176,100 and pays Social Security on every paycheck. A worker earning $220,000 per year reaches the threshold around paycheck 21 and pays no Social Security on the remaining paychecks of the year.

FICA Tax Is Refundable at Year-End

Federal income tax withholding is reconciled on Form 1040. Overpayment results in a refund. FICA works differently. Overpaid FICA from a single employer is generally not refunded directly. One exception: if you worked for two employers and each withheld Social Security on wages that, combined, exceed $176,100, you can claim a credit for the excess on Form 1040. But FICA withheld by a single employer on wages below the wage base is not refundable.

The OBBBA Tip and Overtime Deductions Reduce FICA

They do not. The No Tax on Tips deduction (IRC §224) and No Tax on Overtime deduction (IRC §225) are above-the-line income tax deductions. They reduce federal taxable income on Form 1040, Schedule 1-A. They have no effect on FICA withholding. Social Security and Medicare are calculated on the gross wage before any of these deductions apply. For more on these deductions, see the No Tax on Tips Calculator and the No Tax on Overtime Calculator.

Practitioner Insight (LMN Tax Inc.)

At LMN Tax Inc, we frequently see clients surprised when their last several paychecks of the year show significantly higher net pay. The cause is almost always the Social Security wage base being reached. Once cumulative wages from a single employer pass $176,100, the 6.2% Social Security deduction stops, adding roughly $524 per biweekly paycheck back to net pay at an $8,500 gross. A separate pattern we see is confusion among tipped employees who assume the OBBBA tip deduction reduces their FICA bill. It does not. The deduction reduces income tax only. Social Security and Medicare on tips are calculated on gross tip wages and cannot be waived or reduced through any deduction on Form 1040.

When FICA May Not Apply Normally

  • Self-employed workers: Freelancers, independent contractors, and sole proprietors do not have an employer to match FICA. They pay self-employment tax under SECA instead: 15.3% on net self-employment earnings (12.4% SS + 2.9% Medicare). Both the employee and employer halves are owed by the self-employed person. Half of SE tax is deductible on Form 1040, Schedule 1 as an above-the-line deduction.
  • FICA-exempt categories: Some government employees covered by alternative public pension systems are exempt from Social Security (but not Medicare). Student employees of educational institutions meeting specific IRS criteria may be exempt. Certain nonresident aliens on specific visa types (F-1, J-1, M-1, Q-1 visas) are exempt. Exemptions require proper documentation and employer verification.
  • Multiple employers and excess Social Security: If you work two jobs simultaneously and each employer withholds Social Security independently, combined withholding may exceed what is owed on $176,100 in total wages. The excess is recovered as a refundable credit on Form 1040. Each employer withholds based only on wages it pays and cannot coordinate with other employers.
  • Tipped employees with unreported tips: Tips are subject to FICA. Employees are required to report cash tips to their employer monthly if cumulative tips exceed $20. Tips included in the report are subject to both employee and employer FICA. If a tipped employee fails to report tips and the employer does not withhold FICA, the employee remains liable for both the employee and employer share on those unreported wages.
  • S-Corporation officer compensation: Shareholder-employees of S-Corps receive W-2 wages subject to FICA. Distributions above reasonable compensation are not subject to FICA. Misclassifying reasonable compensation as distributions to avoid FICA is a known IRS enforcement area.

Frequently Asked Questions About FICA Tax

What does FICA stand for?
FICA stands for Federal Insurance Contributions Act. It is the federal law that requires employees and employers to contribute to Social Security and Medicare through payroll withholding. Both the employee and employer each pay a share. The combined rate is 15.3% of covered wages: 12.4% for Social Security and 2.9% for Medicare, split equally between employer and employee.
What is the FICA tax rate for 2025?
For 2025, the employee FICA rate is 7.65% total: 6.2% for Social Security on wages up to $176,100, and 1.45% for Medicare on all wages with no cap. Employers match both rates at the same percentages. Employees earning more than $200,000 in a calendar year also pay an additional 0.9% Medicare surtax on wages above that threshold. Source: IRS Publication 15 (2025).
Does FICA apply to all wages?
FICA applies to most wages paid to employees in covered employment. Social Security applies only up to the annual wage base, which is $176,100 for 2025. Medicare applies to all covered wages with no ceiling. Some categories are exempt, including certain government employees under alternative pension systems, some student employees, and certain nonresident aliens on specific visa types.
Why does my Social Security withholding stop partway through the year?
Social Security withholding stops when your cumulative wages from a single employer reach the annual wage base, which is $176,100 for 2025. Once your year-to-date wages reach this amount, your employer stops withholding the 6.2% Social Security tax for the remainder of the calendar year. Medicare withholding never stops. This is why some employees see higher net pay in the final months of the year.
Is FICA the same as federal income tax withholding?
No. FICA and federal income tax withholding are two separate deductions. FICA covers Social Security and Medicare. The rates are fixed by law and do not depend on your Form W-4. Federal income tax withholding is an estimate of your annual income tax liability, collected each pay period. It is variable and depends on your filing status, W-4 elections, and pay frequency. Both appear on your pay stub, but under different legal frameworks.
Can I opt out of FICA?
Generally no. Most employees in covered employment cannot opt out of FICA. The contributions are mandatory under federal law. Some narrow exceptions exist: certain government employees covered by alternative public pension systems, qualifying student employees, members of specific religious orders, and certain nonresident aliens. If you believe you qualify for an exemption, the employer must obtain and retain the required IRS documentation.
Does the No Tax on Tips or No Tax on Overtime deduction reduce my FICA?
No. The OBBBA deductions under IRC sections 224 and 225 are federal income tax deductions only. They reduce your taxable income on Schedule 1-A of Form 1040. They do not reduce FICA wages. Social Security and Medicare withholding is calculated on gross wages and is not affected by these deductions.
What is the Additional Medicare Tax?
The Additional Medicare Tax is an extra 0.9% Medicare surtax on wages above $200,000 for single filers and $250,000 for married filing jointly. It is an employee-only tax. Employers do not match it. Employers are required to begin withholding the surtax once an employee's wages from that employer exceed $200,000 in a calendar year, regardless of filing status. Any under- or over-withholding is reconciled on Form 1040. Source: IRS.gov, IRC section 3101.
How is FICA different for self-employed workers?
Self-employed workers do not have an employer to match their FICA contributions. Instead, they pay self-employment tax under the Self-Employment Contributions Act. The SE tax rate is 15.3% on net self-employment earnings: 12.4% for Social Security on earnings up to $176,100 and 2.9% for Medicare on all earnings. This covers both the employee and employer share. Self-employed taxpayers can deduct half of the SE tax as an above-the-line deduction on Form 1040, Schedule 1.
What To Do Next

Now that you understand how FICA is calculated and how it differs from federal income tax withholding, use the paycheck calculators to see the exact dollar amounts for your situation. Both calculators apply the 2025 Social Security wage base and Additional Medicare Tax threshold to your specific wages and pay frequency.

Estimate take-home pay with the Hourly Paycheck Calculator or run the Paycheck Calculator for a complete 2025 withholding breakdown including FICA.

To go deeper on the Social Security component specifically, see the Social Security Tax Explained guide. For Medicare specifically, including the Additional Medicare Tax, Form 8959, and dual-income household withholding gaps, see the Medicare Tax Explained guide.

Disclaimer: This guide is for educational purposes only and does not constitute tax or legal advice. Tax rates and thresholds are based on 2025 IRS publications. Consult a qualified tax professional for guidance specific to your situation.
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Written by Munib Ur Rehman  ·  Reviewed by Nausheen Shahid (LMN Tax Inc.)  ·  Published 2026-03-23  ·  Tax Year 2025