Paystub Decoded: Where Is
Your Money Actually Going?
Most workers only look at the net pay hitting their bank account and ignore the rest. That is a costly mistake. Here is exactly how to read your paystub, spot expensive payroll errors, and understand the crucial difference between FICA and Federal tax →.
This article is for you if:
✓You don’t understand why 20% to 30% of your gross pay disappears
✓You confuse mandatory FICA taxes with adjustable Federal income taxes
✓You want to verify you aren’t being overcharged for health benefits
CReviewed by BMT CPA Board·
Sources: IRS, SSA, DOL · For informational purposes only
FICA TAX RATE
7.65%
Mandatory flat tax on all earned income
SSA Data 2026 · Full sources → SEC 06
GROSS
100%
Total earned
NET
~72%
Average take-home
Key Facts
1Pre-tax deductions lower your taxable gross income
2FICA is split: 6.2% Social Security + 1.45% Medicare
3Payroll errors affect 1 in 5 Americans annually
Disclaimer: This article is for informational purposes only and does not constitute tax, legal, or financial advice. Always consult a certified public accountant (CPA).
SEC 02PROBLEM— The Real Cost of Doing Nothing
SECTION 02 — THE PROBLEM
Ignoring the “Deductions” Column Costs You Money
Payroll software is not flawless. If you never review the line-item breakdown between your gross earnings and net deposit, you risk ignoring incorrect health insurance premiums, missed 401(k) employer matches, or a completely unoptimized Federal withholding rate. You cannot optimize what you do not audit.
What Most People Do
Only check the final direct deposit amount
Assume HR calculates everything perfectly
Confuse FICA taxes with Federal taxes
Ignore Year-to-Date (YTD) cumulative totals
The Optimized Approach
Audit deductions on the first check of the year
Verify 401(k) and HSA contributions match reality
Differentiate between pre-tax and post-tax limits
Track YTD amounts for tax planning
WATCH OUT
Do not confuse Pre-Tax with Post-Tax deductions. Pre-tax deductions (like a traditional 401k or HSA) lower the income the IRS taxes you on. Post-tax deductions (like a Roth 401k or union dues) are taken after the government has already taken their cut.
SEC 03EVIDENCE— Data + Sources (E-E-A-T)
SECTION 03 — EVIDENCE & DATA
The Anatomy of a $5,000 Paycheck
Mandatory Taxes (Federal, FICA, State)
Average Net Pay$3,600
Tax Savings by Increasing 401(k) Pre-Tax Contribution
Tax Avoided Annually+$1,200
Source: IRS Publication 15 (Circular E), Social Security Administration — Full source links in SEC 06 below
SEC 04FAQ— People Also Ask
SECTION 04 — FAQ
Frequently Asked Questions
Federal Income Tax goes to the IRS to fund the government, and the amount varies based on how you filled out your W-4 form. FICA (Federal Insurance Contributions Act) is a mandatory flat tax of 7.65% that specifically funds Medicare and Social Security. You cannot adjust FICA.
OASDI stands for Old-Age, Survivors, and Disability Insurance—this is simply the official name for the Social Security tax (6.2%). MEDEE or MED tax stands for the Medicare portion of FICA (1.45%).
Yes, usually. Under a Section 125 Cafeteria Plan, employer-sponsored health, dental, and vision premiums are deducted before Federal and FICA taxes are applied, saving you a significant amount in taxable income.
You should keep your paystubs for exactly one year. Once you receive your final W-2 form in January of the following year, verify that the Year-to-Date (YTD) totals on your final December paystub match the W-2 perfectly. If they do, you can safely shred the paystubs.
SEC 05DECISION— If/Then Framework
SECTION 05 — DECISION SUPPORT
Paystub Audit: Action Plan
Use this 80% probability guide to troubleshoot anomalies on your next payday. Always confirm discrepancies with your payroll department.
Your Situation (IF)Recommendation (THEN)
Federal Tax seems way too high
You are likely getting a massive refund
Submit New W-4
401(k) deduction is missing
You are losing free employer match money
Contact HR Immediately
Earning over $168,600 (2024 limit)
Social security tax caps out at this limit
Expect OASDI to Drop to $0
Gross pay doesn’t match hours worked
Overtime or shift differential missing
Audit Timesheet & Report
EDITOR’S COMMENT — 80% GUIDE
Never assume payroll is infallible. The most lucrative 10 minutes you can spend each month is verifying that your pre-tax deductions (health, HSA, 401k) were properly subtracted before your Federal and FICA taxes were calculated.
Never assume payroll is infallible. The most lucrative 10 minutes you can spend each month is verifying that your pre-tax deductions (health, HSA, 401k) were properly subtracted before your Federal and FICA taxes were calculated.