Most people glance at the bottom line of their pay stub, see the number that landed in their bank account, and move on. That number is the only one that feels real. But the lines above it explain why that number is what it is, and whether it should be higher or lower than it currently is.

A pay stub is not just a receipt. It is a record of decisions you made on a W-4 form, a confirmation that your employer is withholding the right amounts, and a running tally of what you have paid toward taxes and benefits all year. Learning to read it takes ten minutes, and it can catch mistakes that cost real money.

Start With the Two Numbers That Define Everything

Every pay stub is built around a simple subtraction. Gross pay is what you earned before anything was taken out. Net pay is what remains after every deduction has been subtracted. That is the money that actually reaches your account .

For an hourly worker, gross pay is hours worked multiplied by the hourly rate, plus any overtime at the higher rate . For a salaried worker, it is the annual salary divided by the number of pay periods in the year. Someone paid biweekly has 26 pay periods, so a $52,000 salary shows as $2,000 gross on each stub .

The gap between gross and net is where all the complexity lives. And that gap is almost always bigger than people expect, especially on their first real paycheck.

The Mandatory Withholdings You Cannot Avoid

The first deductions on almost every stub are taxes. These are not optional, and they fall into a few distinct categories.

Federal income tax is withheld based on the W-4 form you filled out when you were hired. The amount depends on your filing status and the allowances or adjustments you claimed. If too little is withheld, you may owe money at tax time. If too much is withheld, you get a refund, which is essentially an interest-free loan to the government .

Social Security and Medicare taxes, collectively called FICA, are fixed percentages. Employees pay 6.2% of gross wages toward Social Security, up to an annual wage ceiling, and 1.45% toward Medicare with no cap . Your employer matches these amounts, but only your share appears on your stub. The labels can vary: FICA-SS, OASDI, or simply Social Security for the retirement portion, and FICA-MED or Medicare for the health insurance portion .

State and local income taxes apply depending on where you live. Some states have no income tax at all, and many cities and counties do not impose a local tax. If you see a line for either, it is calculated based on your state’s rules and your earnings .

The Deductions You Chose, and Why Pre-Tax Matters

Beyond taxes, your stub lists benefits and contributions you signed up for. The most important distinction here is whether a deduction is taken pre-tax or post-tax.

Pre-tax deductions come out before income taxes are calculated. That means they lower your taxable income, which reduces the federal and state tax withheld from that same paycheck. Common pre-tax deductions include health, dental, and vision insurance premiums, traditional 401(k) contributions, Health Savings Account contributions, and Flexible Spending Account contributions .

Post-tax deductions come out after taxes are figured. They do not reduce your taxable income today. Roth 401(k) contributions, certain life insurance premiums, union dues, and wage garnishments typically fall into this category .

The practical difference is meaningful. A $100 pre-tax health insurance premium does not reduce your take-home pay by $100. It reduces it by less, because that $100 was never taxed in the first place. A post-tax deduction of the same amount hits your bank account harder.

The Year-to-Date Column Is the One to Watch

Next to every current-period figure, most stubs include a Year-to-Date (YTD) column. These running totals show what you have earned, paid in taxes, and contributed to benefits since January 1 .

YTD figures are useful for a few specific checks. Your YTD gross should roughly match your salary through that point in the year, adjusted for bonuses or overtime. Your YTD federal tax withheld gives you an early read on whether you are on track to owe or get a refund. And your YTD 401(k) contributions tell you whether you are on pace to hit the annual contribution limit.

The YTD column is also where errors become visible. If your YTD gross suddenly jumps by an amount that does not match any raise or bonus, something is wrong. If your YTD Social Security withholding exceeds the annual ceiling for your income level, you may be owed a correction.

What to Check Before You File the Stub Away

A quick review each pay period catches problems before they compound.

Verify the hours and rate. For hourly workers, the hours listed should match the hours worked. Overtime should appear as a separate line at the correct multiplier, usually 1.5 times the regular rate . For salaried workers, the gross should match the expected periodic salary.

Check the deductions against what you enrolled in. If you signed up for a health plan with a $75 premium, that is the number that should appear. A different number means either an enrollment error or a payroll mistake.

Confirm your filing status. The W-4 you submitted determines your federal withholding. If you got married, had a child, or started a side job, your withholding may need to change. The IRS Tax Withholding Estimator can help you check .

Look for anything unfamiliar. An abbreviation you do not recognize is worth a question to payroll. It could be a legitimate benefit you forgot about, or it could be an error. Either way, you should know what it is.

The Stub Is Not the Whole Story at Tax Time

One final point of confusion trips people up every spring. The gross pay on your final pay stub of the year will often be higher than the wages reported on your W-2.

That is not a mistake. Pre-tax deductions like health insurance premiums and traditional 401(k) contributions reduce your taxable wages, and those reduced wages are what appear on the W-2. Your pay stub shows what you earned before those deductions; your W-2 shows what the IRS considers taxable .

Understanding that difference now saves you from a panicked phone call to payroll in April. The stub tells you what you made. The W-2 tells you what you owe taxes on. They are supposed to be different numbers.