Decode every abbreviation on your pay stub. From FIT and SIT to FICA, OASDI, and MED — learn what each code means with real examples and calculations.
Published by the BestPaystubGen Editorial Team — certified payroll professionals, CPAs, and HR experts covering paystubs, payroll compliance, federal and state taxes, W-2 forms, 1099 contractors, FICA, gross vs net pay, and IRS regulations updated for 2026.
Definitions of the most common payroll terms referenced in this article:
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