If you're self-employed, a gig worker, or someone who made extra income on the side this year, the IRS wants its cut soon — and missing the deadline can get expensive fast.
The next estimated tax payment for the 2025 tax year is due Sept. 15.
Anyone who earns income that isn't subject to automatic withholding — freelance clients, DoorDash runs, Etsy sales, consulting gigs, stock dividends — is generally expected to pay as they go, not just in April.
Here's the part that trips people up: the IRS doesn't send a bill or a reminder.
If you don't pay, you often won't hear about it until months later, when a penalty shows up on your account.
That penalty is currently calculated at 7% annualized, and it compounds the longer you wait, according to the IRS.
Underpayment penalties are based on how much you owed versus how much you paid in each quarter, not just your year-end total.
So even if you pay everything in full by April, you can still owe a penalty for skipping September.
Right now, that's money that could have gone toward groceries, a car repair, or literally anything else.
There's a popular myth worth killing: "I'll just pay a lump sum in April and be fine." You won't be fine.
The IRS treats each quarter as its own mini tax bill, and paying late — even by a few weeks — can trigger the charge.
The good news is that most people who owe estimated taxes can avoid the penalty by paying at least 90% of what they owe for the year, or 100% of last year's tax bill, whichever is smaller.
That second option is a lifesaver if your income jumped this year and you don't know what you'll owe.
If you're not sure how much to send, the IRS has a free tool called the Tax Withholding Estimator, and most tax software can calculate quarterly amounts for you.
A simpler move: set aside 25% to 30% of every freelance check in a separate savings account, then pay from there.
High-yield savings accounts are still paying decent rates, so that money can earn a little while it waits.
You can pay online through IRS Direct Pay in a few minutes, and there's no fee for pulling directly from a bank account.
Paying by credit card is possible but comes with a processing fee — usually not worth it unless you're chasing a sign-up bonus.
One more thing worth checking: if you also have a regular W-2 job, you can often avoid quarterly payments entirely by asking your employer to withhold extra from each paycheck.
File a new W-4, bump up the extra withholding line, and the IRS treats it as if you paid on time all year.
The bottom line: Sept. 15 is not a suggestion, and the penalty doesn't care that nobody reminded you.
If you made untaxed money this year, take 20 minutes this week to figure out what you owe and send it.
Final Thoughts
Your future self — the one filing in April — will thank you.