Form W-4
Form W-4 is the IRS form an employee completes when starting a job, telling the employer how much federal income tax to withhold from each paycheck based on filing status, dependents, multiple jobs, and other income or deductions. An employer keeps the completed form on file and uses it to calculate withholding through payroll.
What information goes on Form W-4
Form W-4 asks for filing status (single, married filing jointly, or head of household), then several optional steps for accuracy: Step 2 for a household with two jobs or a working spouse, Step 3 for dependents claimed as tax credits, and Step 4 for other income, deductions, or a flat extra amount withheld each pay period. An employee who skips the optional steps still gets valid withholding calculated from filing status alone, just less precisely tailored to their full tax situation. The form replaced the old allowances system in 2020, so an employee’s allowance count from a pre-2020 W-4 on file does not carry over automatically; employers keep using whichever version is on file until the employee submits a new one.
When to file a new Form W-4
An employee is not required to file a new Form W-4 every year; the one on file stays in effect until they submit a replacement. A new form is worth filing after a major life change, marriage, a new dependent, a second job in the household, or a large refund or tax bill the previous year, since any of those can shift the right withholding amount. An employer cannot fill out or correct an employee’s Form W-4 on their behalf; the employee owns the elections, and the employer’s payroll system simply applies them.
New hires complete Form W-4 as part of onboarding paperwork, before their first paycheck can be calculated correctly. WageTime’s self-onboarding flow collects Form W-4 electronically with e-signatures, so the withholding elections a new hire enters flow straight into payroll setup.
See how WageTime handles new-hire onboardingFrequently asked
What happens if an employee never submits a Form W-4?
The employer must withhold as if the employee is single with no other adjustments, the IRS default treatment, which is usually a higher withholding amount than most employees actually want.
Is Form W-4 the same as Form W-2?
No. Form W-4 is filled out by an employee at hire to set withholding; Form W-2 is issued by the employer after year-end to report what was actually paid and withheld.