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Pay Stub and Paycheck Guides
Updated for 2026 Tax data reviewed 2026-09-16. Sources and methodology
Plain-English explanations of the lines on your pay stub and the most common reasons a paycheck changes.
- What is OASDI on my paycheck?
OASDI is the Social Security portion of payroll tax. Learn why it appears on your pay stub, how it is calculated, and when the deduction may stop. - How to read a pay stub
Learn how to read a pay stub, including gross pay, taxable wages, OASDI, Medicare, deductions, year-to-date totals, and net pay. - Why is my paycheck lower this month?
If your paycheck is suddenly smaller, compare gross pay, taxes, benefits, hours, and payroll corrections. Use this checklist to find the cause. - Why did my paycheck go down in January?
Your January paycheck may change because of new tax tables, benefit premiums, contribution limits, W-4 settings, or year-to-date resets. - What is CA SDI on my paycheck?
CA SDI is a California employee payroll deduction that helps fund disability and paid family leave benefits. Learn what the pay stub line means. - What is NY PFL on my paycheck?
NY PFL is a payroll contribution that supports New York Paid Family Leave. See what the deduction means and how the employee contribution works.