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Pay stub decoder · TY2026

What every line on your pay stub means

Your stub is a dense little tax document written in abbreviations. Here is every one of them, in the order they appear — with the rule or publication behind each, and a link to the calculator that checks it.

27 terms Primary sources cited Last reviewed Jul 28, 2026
SAMPLE STUBBIWEEKLY · TY2026
1REG 80.00 h @ $32.00$2,560.00
1OT 6.00 h @ $48.00$288.00
1GROSS PAY$2,848.00
3SEC 125 — MEDICAL−$180.00
3401(K) 6%−$170.88
2FED INCOME TAX−$243.16
2OASDI 6.2%−$165.42
2MEDICARE 1.45%−$38.69
2STATE INCOME TAX−$88.14
4NET PAY$1,961.71

Illustrative only — a single filer, $2,848 biweekly gross. The numbered ticks map to the four sections below.

The bottom line and the paperwork

Earnings — what you were paid

The top block. Everything else is derived from it.

GROSS Gross pay

Everything you earned before a single deduction — base pay plus overtime, bonuses, commissions, and shift differentials. Every other number on the stub is derived from this one. Check it first: confirm the rate and hours match what you worked.

REG Regular hours

Hours at your base rate, up to your employer's overtime threshold (40/week federally).

OT Overtime

Hours at 1.5× your regular rate. Federally required over 40 hours a week (29 CFR §778.107). Some states add daily thresholds. Check the math →

DT Double time

2× your regular rate. Not a federal requirement — it comes from state law (California's >12-hour rule), union contracts, or company policy.

SHIFT DIFF Shift differential

Extra pay for nights, weekends, or undesirable shifts. Important: it must be folded into your "regular rate" before overtime is computed, which many calculators miss.

PTO / VAC Paid time off

Hours paid but not worked. Accrual and payout-at-separation rules are set by state law and company policy, not federal law. Value your unused hours →

IMPUTED Imputed income

The taxable value of a non-cash benefit — group life insurance over $50,000, personal use of a company car, gym memberships. It inflates your taxable wages without adding cash, which is why your taxes can rise while your net pay doesn't.

Taxes — what governments take

Federal is uniform; state and local vary enormously.

FICA Federal Insurance Contributions Act

Not one tax but two: Social Security (OASDI) and Medicare. A single "FICA" line is the two combined — 7.65% up to the Social Security wage base, then 1.45% on everything above it, because only the Social Security half ever stops.

OASDI / SS Old-Age, Survivors, and Disability Insurance

Social Security tax. 6.2% of wages, and it stops for the year once you hit the wage base — $184,500 in 2026 (up from $176,100), so the maximum you can pay is $11,439. High earners see this line vanish mid-year. Source: SSA contribution and benefit base.

MED / FICA-M Medicare

1.45% of all wages, with no cap — unlike Social Security, it never stops. Source: IRS Topic 751.

ADDL MED Additional Medicare Tax

An extra 0.9% on wages above $200,000 from a single employer. Your employer must withhold it at that threshold regardless of your filing status — which is why married filers sometimes see it withheld when they don't ultimately owe it, and vice versa. Source: IRS Topic 560.

FIT / FWT / FED Federal income tax withheld

An estimate of your annual tax, collected per paycheck, computed from your W-4 using the tables in IRS Publication 15-T. It is not your actual tax — that's settled when you file. A big refund means you over-lent to the government all year.

SIT / SWT State income tax withheld

Nine states withhold nothing on wages: Alaska, Florida, Nevada, New Hampshire, South Dakota, Tennessee, Texas, Washington, and Wyoming. The rest range from a single flat rate to twelve progressive brackets (Hawaii).

LOCAL / CITY Local income tax

Local income taxes are levied by 4,964 taxing jurisdictions across 17 states — Pennsylvania alone accounts for 2,978 of them (2,506 municipalities plus 472 school districts). If you work in Ohio, Pennsylvania, New York City, Maryland, Indiana, or Kentucky, check for this line. Source: Tax Foundation.

SDI / TDI State disability insurance

Employee-paid disability insurance in a handful of states. California's 2026 rate is 1.3% with no wage cap; New York's Paid Family Leave is 0.432%. Most states have neither.

SUI / SUTA State unemployment insurance

Usually paid entirely by your employer. If you see it deducted from your pay, you're likely in Alaska, New Jersey, or Pennsylvania — three states with an employee share.

Deductions — what you elected (or were ordered) to pay

The order these come out in changes your take-home.

401K 401(k) contribution

Traditional 401(k) money is deducted before federal and state income tax — but not before FICA. That's the single most misunderstood line on a pay stub: your Social Security and Medicare are still computed on the full amount. Roth 401(k) is the opposite — taxed now, tax-free later.

SEC 125 / CAF Section 125 / cafeteria plan

Health, dental, and vision premiums taken pre-tax under a Section 125 plan. Unlike 401(k), these do reduce your FICA wages too — which makes a dollar of Section 125 worth more than a dollar of 401(k) in immediate tax savings.

HSA / FSA Health / flexible spending account

Payroll-deducted HSA and FSA contributions get the same treatment as Section 125: exempt from income tax and FICA.

GARN Garnishment

A court-ordered deduction — child support, defaulted student loans, tax levies. Federal law caps how much of your disposable earnings can be taken (DOL Title III).

PRE-TAX vs POST-TAX Deduction ordering

Pre-tax deductions come out before taxes are computed, lowering your taxable wages. Post-tax deductions (Roth 401(k), union dues, garnishments, most life insurance) come out of what's left. The order is what makes two employees with identical gross pay take home different amounts.

The bottom line and the paperwork

Net pay, YTD, and the forms behind the numbers.

NET Net pay

What actually lands in your account: gross minus pre-tax deductions, minus taxes, minus post-tax deductions. See it across pay frequencies →

YTD Year to date

The running total since January 1. Worth a glance every stub — YTD gross is what determines when Social Security stops (at $184,500) and when Additional Medicare starts (at $200,000).

PP / PERIOD Pay period

The stretch of days this check covers — distinct from the pay date, which is usually days later. Biweekly means 26 checks a year; semimonthly means 24. Compare them →

W-4 Employee's Withholding Certificate

The form that drives your federal withholding. Since 2020 it has no “allowances” — it asks for dependents, other income, and deductions directly. Filing a new one is the only way to change your withholding.

W-2 Wage and Tax Statement

The annual summary your employer sends by January 31. Box 1 (taxable wages) is normally lower than your YTD gross, because pre-tax deductions were removed — that gap is not an error.

EXEMPT / NON-EXEMPT FLSA status

Non-exempt employees must receive overtime; exempt employees need not. Status depends on duties and salary level, not job title — and misclassification is common (DOL overtime).

Three things almost everyone gets wrong

1 · A raise does not tax your whole paycheck more

Tax brackets are marginal. Crossing into the 22% bracket means the dollars above that line are taxed at 22% — not everything you earn. See exactly what a raise changes →

2 · 401(k) does not lower your Social Security tax

It lowers income tax only. FICA is still computed on the pre-401(k) amount. Section 125 medical premiums do lower both — so the same dollar deducted two different ways saves you different amounts of tax.

3 · Your W-2 Box 1 is supposed to be lower than your YTD gross

Pre-tax deductions come out before Box 1 is computed. A gap between the two is normal bookkeeping, not a missing paycheck.

If a number looks wrong

Work through it in this order — it isolates the problem fast:

This page explains what the lines mean. It is not tax advice, and it deliberately does not compute state or local withholding — here's why that line exists.