Got paid this year without an employer skimming taxes off the top? Freelance gigs, a side hustle, rental income, a small business – if money came in with no withholding, the IRS still wants its cut, and it doesn’t want to wait until April. That’s what estimated taxes are for, and the last quarterly deadline for 2026 is coming up on January 15, 2027.
Miss it and the IRS can tack on a penalty, even if you’d otherwise get a refund. Here’s who actually has to pay, how much is enough, and the easiest ways to send the money.
Who has to pay estimated tax
The IRS rule of thumb is simple. You generally have to make estimated tax payments if you expect to owe $1,000 or more in tax when you file your return. That catches sole proprietors, partners, S corporation shareholders, freelancers, gig drivers, and anyone else whose income arrives without withholding.
Corporations get their own, lower bar: $500.
There’s one group that can skip the whole thing. If you had no tax liability last year, you were a U.S. citizen or resident alien for the whole year, and your prior tax year covered a full 12 months, you don’t have to pay estimated tax for the current year. Brand-new side hustlers often fall into this bucket in year one – but not year two.
And if you have a regular W-2 job alongside your side income, you might not need quarterly payments at all. You can just ask your employer to withhold more from each paycheck by filing a new Form W-4. There’s a specific line on it for extra withholding. Some people find that far less annoying than four separate payments.
The deadlines
The IRS splits the year into four payment periods, and for 2026 the official Form 1040-ES dates are April 15, June 15, September 15 of 2026, and then January 15, 2027. Yes, the quarters are uneven. The second one is only two months long, because apparently a calendar is just a suggestion.
One useful escape hatch: you don’t have to make the January 15, 2027 payment if you file your 2026 tax return by February 1, 2027, and pay the entire balance due with it. If you’re the file-early type and you know exactly what you owe, that can save you a payment. Most people with lumpy self-employment income, though, are better off just making the January payment.
If a due date lands on a Saturday, Sunday, or legal holiday, paying the next business day counts as on time. And if you mail a payment, the postmark date is what counts.
How much is enough
Nobody knows their exact tax bill in advance, and the IRS knows it. So instead of demanding perfection, it gives you safe harbors. Hit any one of them and there’s no underpayment penalty, even if your estimate turned out wrong. Owe less than $1,000 after withholding and credits? You’re fine. Paid at least 90% of this year’s tax? Fine. Paid 100% of the tax on last year’s return? Also fine – whichever of those numbers is smaller.
That last route is the self-employed favorite. Take last year’s total tax, divide by four, pay that every quarter, and you’re penalty-proof even if this year turns out great. Higher earners get a tougher version of the prior-year rule – the IRS bumps the percentage on them – so read Publication 505 if last year’s income ran well into six figures.
Farmers and fishermen play by special rules too.
To figure your number, use the worksheet in Form 1040-ES. Start with last year’s return as a guide, plug in your expected income, deductions, and credits, and the worksheet spits out your quarterly amount. Estimated too high or too low? Just redo the worksheet before the next quarter and adjust. That’s normal – the IRS expects estimates to move.
One more wrinkle: if your income shows up unevenly – say a huge project landed in the fall – you may be able to use the annualized income method to pay less in early quarters. It’s more paperwork, but it can keep you from overpaying early in the year.
How to pay
Mailing a check with a Form 1040-ES voucher still works, but online is faster and leaves a record. IRS Direct Pay pulls straight from your bank account with no fee. Your IRS online account at IRS.gov/account does the same and shows your payment history. There’s the IRS2Go mobile app, and for businesses there’s EFTPS, the Electronic Federal Tax Payment System.
You don’t even have to stick to quarterly. Pay weekly, monthly, whenever – the IRS doesn’t care, as long as enough money is in by each quarter’s deadline.
What happens if you skip it
Underpay during the year – withholding, estimated payments, or both – and the IRS can charge an underpayment penalty. Here’s the part that stings: it runs per quarter. A giant check in April doesn’t erase a quarter you skipped back in June. And yes, you can owe this penalty in a year where you’re still due a refund. Fun, right?
The penalty works like interest on whatever you underpaid, so waiting makes it worse. Realize in December that you’ve been short all year? The January 15 payment is your chance to stop the clock on that last quarter.
The takeaway
If untaxed income is coming in, run the $1,000 test: will you owe that much or more at filing time? If yes, look at the safe harbors, pick the prior-year shortcut if it fits, and get the January 15 payment on your calendar now. Five minutes with last year’s return and the Form 1040-ES worksheet tells you the number, and Direct Pay takes less time than a coffee run.
Third-party video: Quarterly Estimated Taxes Explained
For a CPA’s walkthrough of how quarterly estimated taxes work in practice, here’s Stephen Lee, The Locum CPA:





