Two jobs, one tax return.
Every employer withholds like it's your only one. This free estimator projects your real April balance across all your W-2 jobs, credits included, and gives you the per-paycheck fix.
Gross pay and per-paycheck federal withholding come straight off each job's most recent paystub.
401(k), HSA, and similar across all your jobs, annual total. The 2026 401(k) employee limit is $24,500 per person, across all plans combined.
Qualifying children for the $2,200 child tax credit. The credit phases out above $200,000 of income ($400,000 joint).
Interest, non-qualified dividends, short-term gains, and similar. Leave 1099 contracting out; self-employment tax needs its own math.
Non-qualified withdrawals from a 401(k) or IRA before 59½. The estimator adds the 10% penalty on top of ordinary tax.
Above-the-line items like deductible IRA or student loan interest, both spouses combined.
Each employer withholds as if its paycheck were your only one, so stacked jobs are structurally under-withheld. On these numbers your effective rate is 18.7% and you would owe about $4,893 next April, even after the $5,301 excess Social Security credit your extra jobs earn you.
Federal estimate for tax year 2026 using the standard deduction and the ordinary brackets in Rev. Proc. 2025-32. Includes the 0.9% Additional Medicare Tax on wages over $200,000 ($250,000 joint), the 10% early distribution penalty, the $2,200 child tax credit with its income phaseout, and the excess Social Security credit when your employers together withhold more than $11,439 (6.2% of the $184,500 wage base). Assumes W-2 wages only; self-employment income, capital gains, itemized deductions, and state tax are out of scope. A planning estimate, not tax advice. Runs entirely in your browser; nothing is stored or sent.
Paystubs in, plan out.
This is the same estimator we run for overemployed clients, turned into a web tool. The under-withholding is structural, which means it is also predictable, and predictable means fixable before the penalty accrues.
Stack the paystubs
Enter each job's gross pay and per-paycheck federal withholding. The estimator annualizes the withholding and computes tax on the combined income, the way the IRS will.
Count the credits
Multiple employers over-withhold Social Security past the one-person maximum, and that excess is a refundable credit. The child tax credit and its phaseout are applied too.
Get the per-paycheck fix
The projected shortfall divided by the paychecks left this year is your W-4 line 4c number. Set it once at one job and April becomes a non-event.
The multi-job playbook.
Why do I owe so much in April when both jobs withhold taxes?
Each employer runs your W-4 as if its paycheck were your only income, so each one applies the standard deduction and the low 10% and 12% brackets to its own wages. Stack two or three jobs and those low brackets get used two or three times while the IRS only allows them once. Your real marginal rate is set by the combined income, so every job is quietly withholding as if you earn far less than you do.
What is the excess Social Security credit?
Every employer must withhold 6.2% Social Security tax up to the annual wage base ($184,500 for 2026) with no knowledge of your other jobs. Work two W-2 jobs with high pay and your combined withholding can blow past the one-person maximum of $11,439. The excess comes back as a refundable credit on Schedule 3 of your return. It is the one place the overemployed setup works in your favor, and this estimator counts it automatically.
How do I fix under-withholding across multiple jobs?
The cleanest lever is Form W-4 line 4c at one job: a flat extra dollar amount withheld each paycheck. Divide your projected shortfall by the paychecks left in the year, which this estimator does for you. Withholding also counts as paid evenly across the year no matter when it happens, so a late-year W-4 change can cure earlier quarters in a way quarterly estimated payments cannot.
Does this estimator handle 1099 or contracting income?
No, it is built for W-2 wages. Self-employment income adds 15.3% SE tax, quarterly estimates, and its own deductions, which need different math. If you have 1099 income on top of your W-2 jobs, our solo 401(k) vs SEP IRA calculator covers the retirement side, and a planning call covers the rest.
Does this calculator store my information?
No. It runs entirely in your browser. Nothing you type is sent to a server, stored, or shared.
Make April a non-event.
We've prepared the overemployed return many times: the excess Social Security credit on one line, the W-4 reset behind it, and no penalty anywhere. Thirty minutes squares your whole picture.