What Comes Out of Your Paycheck and Why
Three things are deducted from every US paycheck by law: federal income tax (withheld as an estimate), Social Security (6.2% up to an annual wage base), and Medicare (1.45%, plus 0.9% more on high earners). Many paychecks also see pre-tax deductions like 401(k) contributions and health insurance premiums, which lower taxable income but also lower take-home pay.
Between federal tax, Social Security, Medicare, and whatever your employer offers in benefits, a $75,000 salary rarely turns into $75,000 spread evenly across the year — the actual take-home is usually 15–30% lower, and most of that gap is entirely explainable line by line.
The taxes required by law
Federal income tax is withheld based on your filing status and the information on your W-4, using tax brackets that increase with income — but it's an estimate spread evenly across the year, not your actual final tax bill (more on that below).
Social Security is a flat 6.2% of wages, up to an annual wage base ($168,600 in 2024) — income above that threshold isn't taxed for Social Security. Medicare is 1.45% of all wages with no cap, plus an additional 0.9% on wages above $200,000 for single filers.
On a $75,000 salary with single filing status, that works out to roughly $8,341 in federal tax, $4,650 in Social Security, and $1,087.50 in Medicare — about $14,079 total, or an 18.8% effective rate, leaving about $60,921 in annual take-home pay before any state tax or pre-tax deductions.
Pre-tax deductions: smaller check, but not lost money
401(k) contributions, health insurance premiums, and similar benefits are typically deducted before taxes are calculated, which lowers both your taxable income and your paycheck — but unlike taxes, that money isn't gone. It's going into a retirement account or paying for coverage you'd otherwise buy yourself.
This is a common source of paycheck confusion: two people with the same salary can see very different take-home amounts purely because one contributes more to a 401(k) or has a more expensive health plan.
Why withholding is a guess, not your actual tax bill
Your employer withholds federal tax using a standard formula that spreads your estimated annual tax liability evenly across every paycheck. It's designed to get close, not to be exact — which is why a tax refund or a balance due at filing time doesn't mean anything went wrong.
If you consistently get a large refund, you're having more withheld than necessary throughout the year; if you consistently owe, less. Adjusting your W-4 can bring withholding closer to your actual liability, which changes each individual paycheck without changing your total tax bill for the year.