How a New Jersey paycheck works
New Jersey has one of the more complicated payslips in the country. The income tax uses five different rate tables rather than one schedule per filing status, and on top of it the employee contributes to four separate state funds: unemployment insurance, the workforce development and supplemental workforce funds, temporary disability insurance and family leave insurance. All four appear as their own lines in the result below, which is why a New Jersey deduction list is longer than most.
Federal income tax withholding
Federal withholding annualises the wage, subtracts the standard deduction for the filing status on Form W-4 Step 1, applies the graduated schedule for that status, and deducts the dependent credit from Step 3. This page models a W-4 with Steps 2 and 4 blank: one job, no spouse income, no other income, no extra withholding. Past the income limit for the status the dependent credit tapers by a set amount for every thousand dollars of excess instead of stopping at a cliff.
Social Security and Medicare
Social Security takes a flat rate on wages up to an annual ceiling that moves with national wage growth, so it stops partway through the year for a high earner. Medicare applies to every dollar, and above a fixed threshold the employer withholds the Additional Medicare tax on the excess, unmatched by the employer and unaffected by filing status.
Five rate tables, not one
Form NJ-W4 asks for a filing status and then offers a wage chart. Single employees and those married filing separately are withheld at the first table. Everyone else defaults to the second. The wage chart exists because New Jersey's tax is calculated on combined household income: a married couple where both partners work would be badly under-withheld on the default table, so the chart moves them to a table with a steeper early rate. An employee who does not fill in the chart stays on the default, which is why some two-earner couples find they owe at filing time.
The calculator lets you pick the table directly. Leave it on the automatic setting to follow the filing status, or select a letter if your Form NJ-W4 wage chart sent you to one. Each table subtracts a fixed allowance for every exemption claimed before the rates apply.
The four employee contributions
Unemployment insurance and the workforce development and supplemental workforce funds are withheld together on wages up to the unemployment wage base, which is low enough that both stop early in the year for most full-time employees. Temporary disability insurance and family leave insurance run on a much higher wage base and are set each year with a published maximum contribution, so a high earner reaches the annual cap and stops. New Jersey is one of the few states that funds unemployment partly from employees; it is also one of the few with both a state disability and a paid family leave programme paid entirely or mostly by workers.
Local income tax
No New Jersey municipality taxes wages. Newark levies a payroll tax on employers rather than employees, so it never appears as a deduction. Residents who commute to New York or Philadelphia are withheld by that state instead and claim a credit on their New Jersey return; this page models work performed in New Jersey.
What the employer pays on top
The employer matches Social Security and Medicare, pays federal unemployment tax, and pays its own experience-rated New Jersey unemployment and disability contributions. Family leave insurance is funded entirely by workers, so the employer pays nothing towards it. Only the employee side is shown.
What this calculator assumes
The figure models a salaried employee paid evenly across the year with a standard Form W-4 and state certificate, and no pre-tax deductions. It leaves out:
- Pre-tax contributions such as a 401(k), health premiums, HSA or flexible spending accounts.
- Extra withholding requested on the federal or state certificate, and the W-4 Step 2 and Step 4 adjustments.
- Bonuses and other supplemental wages, which may be withheld at a flat supplemental rate.
- Employer-side state unemployment insurance, which is priced per employer, and any federal unemployment credit reduction.
- Employees outside the normal Social Security system, such as some public-sector staff and certain visa holders.
Withholding versus your final tax bill
Withholding is a prepayment. The federal and state returns replace these standard assumptions with your real situation: itemised deductions, other income, and credits payroll knows nothing about. One job usually produces a refund; two jobs, a working spouse or investment income often produce a balance due.