Run your employer's own withholding calculation against the W-4 they hold today, then get the Step 4(c) figure that lands your year on the result you actually want — over the paychecks you have left, not a full year you no longer have.
Quick answer
This works out what your paycheck will withhold under the W-4 your employer currently holds, using the IRS Publication 15-T percentage method that payroll systems run, then solves for the Step 4(c) extra-withholding figure that hits your chosen target — break-even, a refund of a set size, or a balance due you are willing to pay.
What this includes
The Publication 15-T (2026) annual percentage method, both the standard and Step 2 checkbox schedules
Every W-4 entry: filing status, Step 2 treatment, Step 3 credits, Step 4(a), 4(b) and 4(c)
Wages from other jobs and a working spouse, entered separately with their own withholding
A bonus still to come, withheld at the 22% supplemental rate rather than your bracket
Self-employment tax, when there is Schedule C profit for the withholding to cover
What it excludes
State and local withholding — this is federal income tax only
Social Security and Medicare, which are fixed percentages a W-4 cannot change
A filled-in or filed Form W-4: the form is signed under penalty of perjury and goes to your employer
Employers who use the wage-bracket tables or an annualised method other than percentage
The 2026 rule most people get wrong: Aiming for the biggest possible refund costs you money. A refund is your own wages, returned without interest up to sixteen months late — the tax you owe is identical either way. The figure worth targeting is close to zero.
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This job's paychecks
Of 26 this year · 11 still to come
$
Before any deduction
$
From your latest stub, including any bonus already paid
$
Federal income tax only — not Social Security or Medicare
The W-4 your employer holds now
How Step 2 is filled in on the certificate this employer has
$
$2,200 per child under 17, $500 per other dependent
$
Income with no withholding that you asked to be covered
$
Deductions above the standard deduction
$
The flat amount currently added to each paycheck
Other jobs and a working spouse
$
Include a spouse's wages on a joint return
$
Full-year figure from their pay stubs
Bonus and income outside your paycheck
$
Withheld at the 22% supplemental rate, not at your bracket
$
Interest, dividends, retirement income
$
Brings self-employment tax with it
$
Quarterly 1040-ES payments, if any
Dependents and pre-tax deductions
$
Traditional, pre-tax, household-wide
$
What do you want at filing?
The plan below solves Step 4(c) to land here
What to do
Add $19 per paycheck to Step 4(c).
Form W-4, Step 4(c) — Extra withholding
Write $19 on line 4(c). Over the 11 paychecks you have left that raises withholding by about $206, which is the gap between where you are heading and your target.
Where the year lands under your current W-4
Projected total tax
$8,330
Projected balance due
$206
Household wages projected$78,000
Withheld so far by this job$4,600
This job's withholding, per paycheck$320
Publication 15-T percentage method, using the W-4 entries above
Remaining 11 paychecks$3,524
Total withholding projected$8,124
Target you chose$0
Refund
What to write on the form
Step 3 — dependent credits$0
What your dependents support
Step 4(b) — deductions$0
Leave blank unless you itemize above the standard deduction
Step 4(c) — extra per paycheck$19
Over your 11 remaining paychecks
Download the form from irs.gov, copy these figures onto it, sign it and give it to your payroll department. It is not filed with the IRS.
This is a plan, not a Form W-4. The W-4 is signed under penalties of perjury and goes to your employer, not to the IRS — download it from irs.gov, copy these figures onto it, and give it to your payroll department.
What each W-4 entry actually does
The W-4 has no line called “withhold more” except 4(c). Everything else changes an input to the employer's calculation, which is why two entries of the same size can move your paycheck by very different amounts.
Entry
What your employer does with it
When to use it
Step 1(c) — Filing status
Chooses which of the three Publication 15-T rate schedules your employer reads, and how much deduction it assumes.
Match the status you will actually file under. It is not a preference.
Step 2 — Multiple jobs or spouse works
Tells the employer its wages are not your only income. Checking box 2(c) makes it withhold on a halved schedule so two jobs together withhold like one return.
Any household with two incomes. Leaving it blank is the single most common cause of a large balance due.
Step 3 — Dependent and other credits
An annual credit amount, divided by your pay periods and subtracted from each paycheck's withholding.
Up to $200,000 of income ($400,000 on a joint return). Above that the credit phases out and the form asks you to leave it blank.
Step 4(a) — Other income
Added to your annualized wages before the rate schedule is applied, so the employer withholds against income it never pays you.
Interest, dividends and retirement income you want covered through payroll instead of quarterly vouchers.
Step 4(b) — Deductions
Subtracted from annualized wages, on top of the standard deduction the schedule already assumes.
Only the amount by which your itemized deductions beat the standard deduction. Entering the whole itemized total double-counts.
Step 4(c) — Extra withholding
A flat dollar amount added to every paycheck, after everything else. Nothing modifies it.
The precise lever. It is how you close a gap you have measured, and the only entry this tool solves for.
What each target costs per paycheck
A single filer paid $3,000 every two weeks, 15 paychecks in, $45,000 of wages and $4,600 withheld so far, no dependents and no other income. Every figure below is produced by the same function the calculator above uses. Note that the projected total tax never moves — only when you pay it does.
Target at filing
Step 4(c) to enter
Cost per paycheck
Extra withheld over 11 checks
Break even
$19
+$19
$206
$500 refund
$65
+$65
$706
$1,000 refund
$110
+$110
$1,206
$2,500 refund
$246
+$246
$2,706
$500 balance due
$0
—
—
The bottom row is the one people find surprising. Accepting a $500 balance due needs no extra withholding at all here, because this filer is already heading for a small shortfall — and the $2,500 refund row costs $246 a paycheck to buy back money that was already yours.
The schedule your employer reads
2026 annual percentage method — single or married filing separately
Payroll annualises your paycheck, subtracts Step 4(b) and $8,600 — $12,900 on a joint return, and nothing at all when the Step 2 box is checked — then reads the row below. The zero-rate band plus that subtraction is exactly the $16,100 standard deduction, which is why the tables produce almost the right answer for a single-job household and go badly wrong for two.
Adjusted annual wage
Tentative withholding
Plus this rate on the excess
Step 2 box checked
$0 – $7,500
$0.00
0%
$0 – $8,050
$7,500 – $19,900
$0.00
10%
$8,050 – $14,250
$19,900 – $57,900
$1,240.00
12%
$14,250 – $33,250
$57,900 – $113,200
$5,800.00
22%
$33,250 – $60,900
$113,200 – $209,275
$17,966.00
24%
$60,900 – $108,938
$209,275 – $263,725
$41,024.00
32%
$108,938 – $136,163
$263,725 – $648,100
$58,448.00
35%
$136,163 – $328,350
$648,100 and above
$192,979.25
37%
$328,350+
The last column is the Step 2 checkbox schedule: the same brackets on half the income. Checking the box on both jobs makes the pair withhold as one return. It works best when the two jobs pay roughly the same — the form itself says the Step 2(b) worksheet is more accurate otherwise.
Why your bonus felt under-withheld
A bonus is a supplemental wage payment. When it is paid separately, or identified separately on a combined payment, your employer may withhold a flat 22% instead of running it through the tables — and almost every payroll system does, because it is far simpler.
At a 12% marginal rate that over-withholds and you get the difference back. At 24%, 32% or 35% it under-withholds, and the gap turns up as a balance due in April. Cumulative supplemental wages above $1,000,000 in a year must be withheld at 37% and your employer has no discretion about it.
Entering the bonus above prices the gap and folds it into the Step 4(c) figure, so the rest of your paychecks close it rather than April doing so.
Step 3 credits, and where they stop
Step 3 is an annual credit figure — $2,200 for each qualifying child under 17 and $500 for each other dependent — which your employer divides by your number of pay periods and takes off each paycheck. It is the entry that most often sits blank when it should not, because people wait for the credit as a refund instead.
Two limits matter. The form restricts Step 3 to filers at or below $200,000 of income, or $400,000 on a joint return, because the credit phases out above that. And withholding stops at zero: credits larger than the tax a job would otherwise withhold buy nothing more through payroll, and the surplus comes back at filing.
If you have two jobs, complete Steps 3 and 4(b) on one W-4 only — the highest-paying one. Claiming the same dependents at both employers halves your withholding twice.
Frequently asked questions
How much extra withholding should I put on my W-4?
Enough to close the gap between the tax you will owe and what your remaining paychecks will withhold, divided by the number of paychecks left. That is what Step 4(c) is for and what this tool solves for. The figure is not a fixed amount for a given salary: someone who finds a $1,200 shortfall in January spreads it over 26 paychecks and needs about $46 each, while the same shortfall found in October spreads over five and needs about $240.
Should I check the box in W-4 Step 2 if I have two jobs?
Check it on both W-4s when there are exactly two jobs and they pay roughly the same. It tells each employer to withhold on a halved rate schedule, so the two together withhold as one return. When the jobs pay very differently the form's own instructions say the Step 2(b) Multiple Jobs Worksheet is more accurate, because the halved schedule assumes the second job is about the same size. Never check it when you only have one job — it will withhold far too much.
Can I change my W-4 in the middle of the year?
Yes, as often as you like. A W-4 takes effect on the next payroll run after your employer processes it, and it only affects future paychecks — which is why a midyear correction has to be larger per paycheck than the same correction made in January. Enter how many paychecks you have already received and the plan sizes the change to the ones that remain.
Why did I owe tax even though I claimed zero allowances?
Allowances no longer exist. The W-4 was rebuilt in 2020 and there is no line to claim them on the current form; if you are thinking of a certificate from 2019 or earlier, your employer is still using it under the old rules. On the current form the equivalent lever is Step 4(c), and the usual cause of owing is a second income the first employer knows nothing about, which is what Step 2 exists to fix.
Does a bigger refund mean I paid less tax?
No. Withholding changes when you hand over the money, never how much you owe. The tax on a given year's income is the same whether you get a $4,000 refund or write a $200 cheque — the refund is simply your own wages coming back, without interest, up to sixteen months after you earned them. The scenario table on this page shows the projected total tax staying identical across every target.
Should I use this or the IRS Tax Withholding Estimator?
Use both if you can. This page runs the same Publication 15-T percentage method your employer runs and shows the arithmetic, which the IRS estimator does not. The IRS estimator handles cases this does not — pensions with their own Form W-4P, multiple jobs with very different pay periods, and part-year employment — and it is the option the form itself points self-employed filers to. Neither one files anything for you.
What if I am self-employed as well as employed?
You can cover self-employment tax through payroll rather than quarterly vouchers, and it is often simpler — withholding is treated as paid evenly across the year, so it cannot fall foul of a missed installment date the way an estimated payment can. Enter your Schedule C net profit above and the plan includes the self-employment tax in what the withholding has to cover. Compare the result against the quarterly planner before committing.
Educational estimate only. This runs the Publication 15-T percentage method, which is what most payroll systems use, but employers may use the wage-bracket tables or a different permitted method and your actual paycheck can differ. It does not produce or file a Form W-4 — only your employer can act on one, and only you can sign it. Full disclaimer.