How to read your pay stub, line by line.

Most people glance at the final number on their pay stub and file it away. But a pay stub is the clearest record you have of whether you are being paid correctly, and the gap between your salary and your take home pay is not random. Here is what every section means, working from the top down.

Gross pay, the number before anything is taken out

Gross pay is what you earned this period before a single deduction. For an hourly worker, that is your rate times your hours, plus any overtime, which is generally one and a half times your regular rate for hours over forty in a week. For a salaried worker, it is your annual salary divided by the number of pay periods. If you worked overtime, tips, or a bonus this period, this is where to confirm it actually showed up.

Taxes withheld, the biggest bite

Federal income tax. Withheld based on what you put on your W-4. If too much comes out, you get a refund at tax time. If too little, you owe. The W-4 is the dial that controls this, and you can change it any time your life changes.

FICA, which is Social Security and Medicare. These are usually listed separately. Social Security is withheld at 6.2 percent of your wages up to an annual cap, and Medicare at 1.45 percent with no cap. Your employer pays a matching amount you never see. This is not optional and not based on your W-4.

State and local income tax. Depends entirely on where you live and work. Some states have none, others have several layers. If you recently moved or work across state lines, this is a line to watch closely.

Pre-tax deductions, the ones that lower your taxable pay

These come out before income tax is calculated, which is why they quietly save you money. Common ones are your share of health, dental, and vision insurance premiums, contributions to a traditional 401(k) or 403(b), HSA or FSA contributions, and sometimes commuter benefits. A dollar you route here is a dollar that is not taxed this year, which is the whole point of them.

Post-tax deductions, taken after taxes

These come out of what is left after taxes. Think Roth 401(k) contributions, wage garnishments, union dues in some setups, or charitable giving through payroll. They do not lower your taxable income, they just route money somewhere before it hits your bank account.

Net pay, the number you actually take home

Net pay is gross minus every tax and deduction above. This is what lands in your account. If the math from gross to net does not roughly add up, that is your signal to ask payroll, because that is exactly where errors hide.

Year to date, the running totals that matter at tax time

Most stubs carry a YTD column showing the cumulative total for the year. This is worth a look because it is what flows onto your W-2. Compare your final stub of the year against your W-2, and check that your 401(k) total is tracking toward the annual limit if you are trying to max it. It is much easier to catch a problem in October than the following April.

The four lines to check every period

You do not need to audit the whole thing each time, but a thirty second scan pays off. Confirm your hours and any overtime are right. Confirm your pay rate did not change unexpectedly. Confirm your benefit deductions match what you signed up for. And glance at net pay to see it is in the range you expect. Quiet errors, a missed overtime multiplier, a benefit you canceled still being deducted, tend to repeat every period until someone notices.

General information, not tax or legal advice, and payroll rules vary by state and employer. For your situation, your HR or payroll team is the right first stop. If you want a pay stub scanner that flags anomalies and tracks the trend over time, in English or Spanish and entirely on your device, Plantilla does exactly that.

— JC Mobile App Studio