Quarterly Estimated Tax

Calculate what to send the IRS each quarter. Avoid underpayment penalties.

Expected net self-employment profit this year $120,000

Revenue minus business expenses, before any tax.

Tax already withheld or paid this year $0

Include W-2 withholding from a day job and any estimated payments already sent.

Federal marginal rate 22%

State rate 5%

Quarters remaining this year 4

Send each quarter

$0 total estimated for the year, $0 remaining after payments

Self-employment tax

15.3% on 92.35% of profit

Income tax, federal + state

at 22% federal and 5% state

Payment schedule by due date

💡 Set-aside rule

Set aside about 0% of every dollar you earn.

Quarterly Estimated Tax Calculator

Nobody withholds tax from a business owner's income, so the IRS expects four payments through the year and charges an underpayment penalty when they come up short. Owners get this wrong in two ways. Some skip the payments and meet a large April bill plus penalty and interest. Others set aside a round number like 20% and forget self-employment tax entirely, which by itself is 15.3% before a dollar of income tax. The number that matters is the one you send each quarter, and very few owners have computed it.

Enter your expected net self-employment profit for the year (revenue minus expenses) and any tax already withheld or paid, including W-2 withholding from a day job and estimates already sent. Set your federal marginal rate and state rate with the sliders, then choose how many quarters remain. The calculator computes self-employment tax using 2026 figures: 12.4% Social Security on 92.35% of profit up to the $184,500 wage base, plus 2.9% Medicare on the full amount. It then applies your federal and state rates to profit less half of that self-employment tax, adds everything up, subtracts what you have paid, and divides the remainder by the quarters left. The headline is what to send each quarter. The two stats are self-employment tax and combined federal plus state income tax. The insight box converts the total into a set-aside percentage of every dollar you earn, a monthly figure, and the safe harbor rule: pay 100% of last year's tax (110% if your AGI was over $150,000) and the penalty goes away.

The chart is a stacked bar for each due date: April 15, June 15, September 15, and January 15, with self-employment tax in sage, federal income tax in gold, and state tax in muted green. Four even bars means you are on schedule. If one or two bars carry the entire load, you are catching up late and should raise your set-aside now.

In Predictable Income, business income is one of three streams, and it is the only one where nobody withholds for you. Operators treat the quarterly payment as a fixed bill: they move the set-aside percentage into a separate account with every deposit and pay on the due date. Re-run this calculator when each quarter closes, when profit runs ahead of plan, and whenever withholding from a job changes.