W-4 and M-4 explained for a new hire (with F-1 notes)

Every new hire in Massachusetts completes two withholding forms: the federal W-4 and the state M-4. Together they tell your employer how much income tax to pull from each paycheck. For F-1 students, there is a third layer: special W-4 instructions that apply to nonresident aliens, set out in IRS Notice 1392. This guide walks through both forms, explains the F-1 wrinkle, and covers what to expect on the pay stub.

SimpleStub makes pay stubs. It does not file taxes, remit withholding, or give tax or immigration advice. Confirm residency status and form instructions with a qualified advisor before relying on the exemptions below.

What is the W-4 and why does it matter?

The W-4 is the IRS form every new hire gives their employer so the employer knows how much federal income tax to withhold from each paycheck. The employer feeds the W-4 data into the IRS Pub 15-T percentage method to calculate withholding. Getting it right matters: too little withheld means a tax bill at filing; too much means a refund you waited a year to receive.

The current W-4 (redesigned in 2020) has five steps:

• Step 1: Filing status and name. Most employees choose Single, Married filing jointly, or Head of household.
• Step 2: Multiple jobs or working spouse. Complete only if applicable.
• Step 3: Claim dependents.
• Step 4: Other adjustments (other income, deductions, extra withholding).
• Step 5: Sign and date.

Only Steps 1 and 5 are required for everyone else. Steps 2 through 4 are optional refinements.

What are the special W-4 rules for F-1 nonresident aliens?

F-1 students who are nonresident aliens for tax purposes follow IRS Notice 1392, which overrides some of the standard W-4 instructions in three ways.

First, the filing status in Step 1 must be Single or Married filing separately, even if the employee is married. Nonresident aliens cannot use the Married filing jointly or Head of household boxes.

Second, if the employee has more than one job, they generally cannot use the Step 2 checkbox method. Notice 1392 provides a separate worksheet for multiple-job NRA employees.

Third, on Step 4(b), the employee may not claim the standard deduction adjustment that residents use. Instead, they write "NRA" on Step 4(b) or on the dotted line on that row, which flags the special withholding calculation the employer must apply.

The result is that NRA employees typically have somewhat more federal income tax withheld than a resident at the same income level. That reflects how nonresident aliens are taxed: they cannot take the standard deduction on their federal return.

F-1 students are generally nonresident aliens for their first five calendar years of US presence. After that, the Substantial Presence Test determines residency. Once an F-1 student becomes a resident alien, the standard W-4 instructions apply and the "NRA" notation is no longer needed.

What is the M-4 and how does it work?

The M-4 is Massachusetts' equivalent of the W-4. It tells your employer how much Massachusetts income tax to withhold. Massachusetts taxes income at a flat 5.0% rate. (A 4% surtax applies only to the portion of taxable income above $1,107,750 in 2026; nearly all new hires will never reach it.)

The M-4 asks for your personal exemptions. Massachusetts allows a personal exemption per filer and additional exemptions for dependents and certain situations. More exemptions claimed means less withheld per paycheck, though the flat rate stays the same.

There is no separate NRA version of the M-4. F-1 students fill it out the same way as any other new hire. Massachusetts income tax is still withheld regardless of immigration status or FICA exemption.

What does each form affect on the pay stub?

The W-4 and M-4 only affect income tax withholding. FICA (Social Security and Medicare) is calculated separately and is not touched by either form. For an F-1 student who is a nonresident alien, FICA is exempt entirely on F-1-authorized work, so those lines simply do not appear on the stub.

What does Massachusetts Paid Family and Medical Leave look like on the stub?

MA PFML is a post-tax deduction, not a tax. It appears on the stub as a separate line after income taxes. For employers with 25 or more covered individuals, the employee share is up to 0.46% of wages (0.28% medical plus 0.18% family). For smaller employers, the full 0.46% is employee-funded. Either way, the deduction stops once the employee's year-to-date wages hit the Social Security wage base ($184,500 for 2026). PFML does not change based on W-4 or M-4 elections.

Massachusetts law (M.G.L. c. 149, s. 148) requires that the pay stub show every deduction each pay period, including PFML, with year-to-date totals.

What should a new hire verify before the first paycheck?

Before your first pay stub arrives, confirm:

• You submitted both the W-4 and the M-4 to your employer. Missing either form will trigger default withholding, which may not match your situation.
• If you are an F-1 NRA student, your W-4 uses Single filing status and includes "NRA" in Step 4(b), per IRS Notice 1392.
• Your employer is not withholding Social Security or Medicare if your F-1 FICA exemption applies.
• The PFML deduction appears as a post-tax line, not as a tax.

If Social Security or Medicare was withheld in error, ask your employer to correct and refund it first. If the employer cannot, the IRS provides a process to claim a refund directly using Form 843 and Form 8316.