Payroll statements can look like they were written in a different language. FIT, OASDI, MED EE, SIT, CASDI, EE PRE, ER MATCH and YTD may all appear on one page, and every payroll provider uses slightly different abbreviations.
The easiest way to read the statement is to group the codes into four categories: earnings, taxes, benefits, and year-to-date totals.
The ePaystubs pay stub abbreviations guide is a useful reference when your employer uses unfamiliar labels.
FIT, FWT and FITW
These abbreviations generally refer to federal income tax withholding.
The employer calculates federal withholding using taxable wages, payroll frequency, Form W-4 information, and IRS withholding methods.
Common variations include:
- FIT
- FWT
- FITW
- FED WH
- Federal Tax
If this line changed unexpectedly, compare your taxable wages and W-4 information. See FIT or FWT on a pay stub.
FICA
FICA is the federal payroll-tax framework that includes Social Security and Medicare taxes.
Some payroll systems show one combined label. Others separate the two components.
The employee-side ordinary rates are generally:
- Social Security: 6.2% on covered wages up to the annual wage base
- Medicare: 1.45% on covered wages, subject to separate Additional Medicare Tax rules for higher earners
See FICA on a pay stub for the detailed calculation.
OASDI or Social Security
OASDI stands for Old-Age, Survivors, and Disability Insurance. On a pay stub, it usually refers to the Social Security portion of FICA.
Possible labels include:
- OASDI
- SS
- SOC SEC
- Social Security
- FICA SS
For 2026, Social Security tax applies only up to the annual taxable wage base. A high earner may therefore see the employee Social Security deduction stop later in the year once covered wages reach the limit.
See OASDI on a pay stub.
MED, Medicare, MED EE and MED ER
MED usually refers to Medicare tax.
EE often means employee.
ER often means employer.
So MED EE can mean the employee-side Medicare amount, while MED ER can represent the employer-side amount. Only the employee deduction normally reduces the employee’s net pay.
See MED on a pay stub for examples.
SIT, SWT and SITW
These commonly refer to state income tax withholding.
Payroll providers use different abbreviations, so the same tax might appear as:
- SIT
- SWT
- SITW
- State Tax
- State WH
The amount depends on the employee’s state, taxable wages, withholding certificate, and applicable state rules.
SDI and CASDI
Some states have state disability insurance or related payroll programs.
California employees may see:
- CA SDI
- CASDI
- SDI EE
- CA SDI EE
These are not federal taxes. They relate to the state’s disability-insurance payroll system.
See SDI and CASDI on a pay stub for California-specific details.
EE and ER
These two abbreviations cause a lot of confusion.
EE usually means employee.
ER usually means employer.
Example:
Health EE: $120
Health ER: $350
The $120 may be the employee deduction, while $350 is the employer contribution. The employer amount can be shown for transparency without being deducted from the employee’s net pay.
The same labeling pattern can appear for retirement contributions, insurance, taxes, or benefits.
401(k), EE PRE and Roth
A retirement deduction can appear under many labels:
- 401K
- 401K EE
- EE PRE
- PRE-TAX 401K
- ROTH 401K
- 401K ER MATCH
Traditional pre-tax and Roth contributions are not taxed in exactly the same way, so do not assume they affect federal taxable wages identically.
See 401(k) on a pay stub.
PRE-TAX and POST-TAX
A pre-tax deduction is taken before one or more applicable taxes are calculated. A post-tax deduction is taken after the relevant taxes have been calculated.
The exact tax treatment depends on the benefit.
This distinction helps explain why gross pay can be higher than federal taxable wages.
YTD
YTD means year to date.
It is a running total, not another current deduction.
If a pay stub shows:
Current Medicare: $36
YTD Medicare: $720
only $36 belongs to the current payroll. The $720 is the accumulated total for the year.
See current vs. YTD on a pay stub.
GROSS, TAXABLE and NET
These three concepts are different.
Gross pay: earnings before taxes and deductions.
Taxable wages: the amount subject to a particular tax after applicable adjustments.
Net pay: the amount remaining after employee taxes and deductions.
One employee can legitimately have three different figures on the same statement.
Why two employees can have different deductions
Coworkers with the same hourly rate can receive different net pay because of:
- Different W-4 elections
- Different state withholding
- Different health coverage
- Different 401(k) percentages
- HSA or FSA contributions
- Garnishments
- Voluntary deductions
- Different hours or overtime
Net pay is personal to the employee’s payroll situation.
What to do when you do not recognize a code
Use this process:
- Look for the same abbreviation on an earlier pay stub.
- Check the employer’s payroll or benefits glossary.
- Compare the amount with benefit elections.
- Determine whether the code is in the tax, deduction, or employer-contribution section.
- Ask payroll for the exact internal definition.
Do not assume a deduction is illegal merely because the abbreviation is unfamiliar.
Final takeaway
Most paycheck codes become easier once you know the basic patterns. FIT relates to federal withholding, OASDI to Social Security, MED to Medicare, SIT to state withholding, EE to employee, ER to employer, and YTD to cumulative totals.
When an employer needs a clear statement of legitimate payroll activity, a pay stub generator can help organize real earnings, taxes, deductions, employer contributions, and net pay into a readable format.