Your salary offer says $80,000. Your first paycheck feels much smaller. This guide explains every line on that paycheck — federal withholding, Social Security, Medicare, state tax, and pre-tax benefit deductions — so you know exactly where your money goes and how to get more of it home.
The Anatomy of a US Paycheck
- Gross Pay: Your salary or hourly pay before anything is removed.
- Federal Income Tax Withholding: Based on your W-4 form and the IRS withholding tables. Adjusting your W-4 changes this amount.
- Social Security Tax: 6.2% of wages up to $176,100 (2025). Stops at the cap — a meaningful benefit for high earners.
- Medicare Tax: 1.45% with no cap. Plus 0.9% on wages over $200,000 (single).
- State Income Tax: Varies by state. Zero in Florida, Texas, etc. Up to 13.3% in California.
- Pre-Tax Deductions: 401(k), HSA, FSA, medical/dental premiums — these reduce taxable income before federal and state tax is calculated.
- Post-Tax Deductions: Roth 401(k), some life insurance, garnishments — deducted after tax.
Pre-Tax Benefits: The Biggest Lever
Contributing to pre-tax accounts reduces your taxable income before federal and most state taxes are calculated:
- 401(k): Max $23,500 in 2025 ($31,000 if age 50+). Reduces federal and most state taxable income. No FICA savings.
- HSA (Health Savings Account): $4,300 single / $8,550 family (2025). Reduces federal income tax AND FICA — one of the most tax-efficient accounts available.
- FSA (Flexible Spending Account): Up to $3,300. Use-it-or-lose-it but reduces FICA too.
- Employer health insurance premium (employee share): Usually pre-tax, reducing FICA and income tax.
Example 1 — $60,000 Salary, Single, No State Income Tax
| Gross Salary | $60,000 |
| 401(k) contribution (6%) | −$3,600 |
| Federal Taxable Income | $56,400 |
| Standard Deduction | −$15,750 |
| Federal Income Tax (~10/12/22%) | −$5,720 |
| Social Security (6.2%) | −$3,720 |
| Medicare (1.45%) | −$870 |
| State Tax (Florida: $0) | $0 |
| Annual Take-Home | ~$46,090 |
| Monthly | ~$3,841/mo |
Example 2 — $100,000 Salary, Single, California
| Gross | $100,000 |
| Federal Tax (~$14,070) | −$14,070 |
| Social Security (6.2%) | −$6,200 |
| Medicare (1.45%) | −$1,450 |
| CA State Tax (~9.3% bracket, effective ~6.5%) | −$6,500 |
| CA SDI (0.9%) | −$900 |
| Annual Take-Home | ~$70,880 |
| Monthly | ~$5,907/mo |
The same $100K salary in Texas (no state income tax) takes home ~$77,380/yr — a $6,500 difference.
How to Increase Your Take-Home Pay
- Max your HSA first: It's the only account that avoids federal income tax, FICA, AND grows tax-free for medical expenses. A triple tax benefit.
- Adjust your W-4: If you got a large refund last year, you're loaning the government money interest-free. Adjusting your W-4 gives you more per paycheck.
- Consider living in a no-income-tax state: If your employer allows remote work, Texas vs California is a $6,500–$20,000+/yr difference on a $100K–$300K salary.
- Defer income: 401(k) contributions reduce current-year taxable income. If you're in the 22% bracket, every $1,000 contributed saves $220 in federal tax.
Calculate your US take-home pay
Open Take-Home Calculator →Why is my federal withholding different from my actual tax?
Your employer estimates your annual tax and withholds accordingly based on your W-4. When you file your return, you reconcile — if they withheld too much, you get a refund. Too little, you owe. A W-4 with the right number of allowances / additional withholding settings minimises the difference.
Does my 401(k) contribution reduce FICA taxes?
Traditional 401(k) contributions reduce federal and state income tax, but NOT FICA (Social Security + Medicare). HSA contributions made via payroll deduction do reduce FICA. This is why maxing your HSA before your 401(k) is generally recommended if you're eligible.
Source: IRS Publication 15-T, 2025. State rates approximate. Not tax advice.