Most people glance at the bottom line of their paycheck — the net pay — and ignore everything above it. That’s a mistake worth real money. Your pay stub is a detailed receipt showing exactly where your earnings go: taxes, benefits, retirement contributions, and deductions you may not even remember agreeing to. Understanding it takes ten minutes and pays off every payday for the rest of your career.

Here’s a line-by-line tour of a typical US pay stub, what each section means, and the red flags to watch for.

The Big Three: Gross Pay, Deductions, Net Pay

Every stub boils down to a simple equation: gross pay minus deductions equals net pay (your “take-home”). Gross pay is what you earned — hourly wages times hours, or salary divided by pay periods. Net pay is what hits your bank account. The gap between them, often 20–35 percent, is where the interesting details live.

Check gross pay first every payday. If you worked overtime or got a raise, confirm it’s reflected. Payroll errors are more common than people think, and they’re much easier to fix the week they happen than months later.

Federal Tax Withholding: Where the Biggest Chunk Goes

You’ll typically see “Federal Income Tax” or “FIT” withheld. This isn’t your final tax bill — it’s a prepayment toward it, calculated from your W-4 form and IRS withholding tables. Too little withheld and you’ll owe in April (possibly with penalties); too much and you’re giving the government an interest-free loan until your refund.

The W-4 you filled out when hired controls this. Life changes — marriage, kids, a second job, a working spouse — should trigger a W-4 review. The IRS Tax Withholding Estimator tells you in minutes whether your withholding matches your actual liability. If you consistently get big refunds, you’re over-withholding; adjust and put that money to work monthly instead.

FICA: Social Security and Medicare

These are non-negotiable federal payroll taxes, shown as “FICA,” “Social Security,” and “Medicare”:

  • Social Security: 6.2 percent of wages up to the annual wage cap ($176,100 in 2025; adjusted yearly). Your employer matches it. Earn above the cap and withholding stops for the rest of the year — a nice late-year bump for high earners.
  • Medicare: 1.45 percent of all wages, no cap, employer-matched. High earners pay an additional 0.9 percent above $200,000.

You can’t adjust these — but you should verify the math occasionally, especially after job changes. Errors here are rare but not unheard of. You can also check your lifetime earnings record through the Social Security Administration’s official site.

State and Local Taxes

Depending on where you live, you’ll see state income tax, and possibly city or county taxes (looking at you, New York City and Philadelphia). Nine states have no income tax at all. If you work in one state and live in another, check that withholding reflects the right jurisdiction — multi-state workers are a classic payroll-error zone. This is also where setting aside taxes as a self-employed person differs sharply: employees get withholding automatically, freelancers must do it themselves.

Pre-Tax Deductions: The Money-Savers

These reduce your taxable income — you pay less tax because they’re subtracted before taxes are calculated:

  • 401(k)/403(b) contributions: your retirement savings, often with an employer match. If you’re not contributing enough to capture the full match, you’re declining free money — fix this before anything else.
  • Health insurance premiums: your share of medical, dental, and vision coverage.
  • HSA/FSA contributions: health savings or flexible spending accounts. HSA money is triple tax-advantaged and rolls over; FSA money is mostly use-it-or-lose-it.
  • Commuter benefits: pre-tax transit or parking, if your employer offers them.

Maximizing pre-tax deductions is one of the simplest legal ways to lower your tax bill — money you’d spend anyway, shielded from taxes. Review these during open enrollment, not just when hired.

Post-Tax Deductions and Other Lines

These come out after taxes: Roth 401(k) contributions (taxed now, tax-free later), disability or supplemental life insurance, union dues, charitable giving, and wage garnishments if applicable. Also watch for:

  • PTO balances: many stubs show vacation and sick time accrued and used. Track this — “use it or lose it” policies quietly erase earned time.
  • YTD (year-to-date) totals: the running annual sum of each line. Essential at tax time and for spotting gradual errors.
  • Employer contributions: some stubs show what your employer pays toward your benefits — useful context for your total compensation.

If any deduction looks unfamiliar, ask HR or payroll. Mystery deductions are worth a five-minute email; they range from harmless (a renamed benefit) to fixable errors. Understanding every line is part of building a budget that actually works — you can’t plan spending accurately without knowing your true take-home.

Red Flags to Watch Every Payday

  • Gross pay doesn’t match hours worked or your salary ÷ pay periods
  • Sudden changes in withholding with no W-4 update from you
  • Benefit deductions for coverage you declined or that ended
  • Missing employer 401(k) match you were promised
  • PTO balance dropping without you taking time off

Keep digital copies of every stub — most payroll portals allow PDF downloads. You’ll need them for loan applications, tax disputes, and verifying W-2s in January.

Overtime, Bonuses, and Irregular Pay

If your pay varies — overtime, commissions, tips, or bonuses — your stub deserves extra attention. Overtime must be paid at 1.5x your regular rate for hours over 40 in a week (federal law, with some exemptions), and the stub should show the overtime hours and rate separately. Bonuses are often withheld at a flat 22 percent federal rate, which may differ from your actual tax bracket — a big bonus can mean over-withholding you’ll recover at tax time, or under-withholding if you’re in a higher bracket. Tipped workers should verify reported tips match reality, since underreporting creates tax trouble later. Whenever pay is irregular, compare the stub against your own records that same week; memory fades fast and payroll departments correct errors much more willingly within the current pay period.

Conclusion

Your pay stub tells the full story of your compensation: gross pay at the top, federal and FICA taxes in the middle, pre-tax deductions quietly saving you money, and net pay at the bottom. The ten-minute habit — verify gross pay, scan for unfamiliar deductions, check PTO and YTD totals — catches errors early and surfaces opportunities like under-claimed 401(k) matches or over-withholding. It’s your money; the stub is the receipt. Read it.

Frequently Asked Questions

Why is my net pay so much lower than my salary?

Federal income tax, Social Security, Medicare, state/local taxes, and benefit premiums typically consume 20–35 percent of gross pay. Pre-tax deductions like 401(k) contributions also reduce take-home while building your wealth.

What is the difference between gross pay and net pay?

Gross pay is your total earnings before anything is removed. Net pay (take-home pay) is what remains after taxes, benefit premiums, and other deductions — the amount actually deposited.

How do I know if my tax withholding is correct?

Use the IRS Tax Withholding Estimator online — it compares your withholding to your projected tax bill. Big annual refunds mean you’re over-withholding; owing large amounts (or penalties) means you’re under-withholding.

What should I do if my paycheck looks wrong?

Contact your payroll department or HR immediately with specifics (pay period, expected vs. actual amounts). Keep copies of your stubs — errors are far easier to fix promptly than months later.