The difference between gross pay and net pay
Gross pay is your salary or wages before any deductions. Net pay — sometimes labelled 'take-home pay' — is what actually lands in your bank account after federal tax, state tax, FICA taxes, and any pre-tax benefits are withheld. The difference typically ranges from 25% to 40% of gross pay depending on your state, filing status, and benefit elections.
What each paycheck deduction pays for
| Deduction | Rate / Amount | What It Funds |
|---|---|---|
| Federal income tax | Varies by bracket + W-4 elections | IRS; withheld in advance of April tax filing |
| State income tax | 0% (TX, FL, WA…) to ~13.3% (CA top bracket) | State government; varies widely by state |
| Social Security (OASDI) | 6.2% of wages up to the annual wage base | Social Security retirement and disability benefits |
| Medicare (HI) | 1.45% of all wages (no cap); +0.9% above $200K | Medicare hospital insurance |
| 401(k) / 403(b) contribution | Your elected percentage (e.g. 6%) | Your retirement account — reduces federal taxable income |
| Health / dental / vision premium | Your share of the plan cost | Employer group plan; typically pre-tax under Section 125 |
How Social Security and Medicare taxes are capped
Social Security tax (6.2%) applies only up to the annual wage base ($176,100 for 2025). Above that threshold, no further Social Security tax is withheld for the year. Medicare (1.45%) has no wage-base cap — it applies to every dollar of wages, and earners above $200,000 (single) or $250,000 (married filing jointly) pay an additional 0.9% Medicare surtax.
How to estimate your net pay
Net Pay = Gross Pay − Federal Tax − State Tax − Social Security − Medicare − Pre-Tax Benefits
How your W-4 form controls tax withholding
Your W-4 (Employee's Withholding Certificate) tells your employer how much federal tax to withhold from each paycheck. Filing as 'Single' with no adjustments typically produces withholding close to your actual tax liability. The 2020 W-4 redesign retired the old 'allowances' system — today, under-withholding usually comes from skipping Step 2 (Multiple Jobs or Spouse Works) or overstating the dollar amounts in Steps 3-4 (Dependents, Other Adjustments), and the result is the same: you owe a balance in April. Under-withholding by more than $1,000 may also trigger an IRS underpayment penalty. The fix is to revisit your W-4 after any life change: marriage, a new child, or a significant side income.
How pre-tax 401(k) contributions cost you less
Whether a big tax refund is a good thing
A large April refund means you over-withheld throughout the year — you gave the IRS an interest-free loan. A small refund or a small balance due means your withholding was accurate. The goal is not to maximize the refund; it is to minimize the interest-free loan to the government while also avoiding an underpayment penalty. Many people prefer a modest refund (~$500) as forced saving — that's a valid behavioral choice, but not an investment strategy.
Read your own pay stub line by line
How state income tax changes your take-home pay
Sit with the ideas.
You start a job at $75,000/year in a state with 5% income tax. You elect 6% to your 401(k). Your first paycheck shows a 'Federal Income Tax' withholding that seems too high. Which action is most appropriate?