If you're self-employed, the IRS doesn't wait until April to get paid.
It wants its money four times a year, and the next installment lands on September 15.
Miss it, and the penalty compounds quietly in the background while you're busy running your business.
Here's the trap: most freelancers and gig workers either skip quarterly payments entirely or send in a number pulled from thin air.
The IRS charges interest on underpayments, and that rate has been hovering around 7% to 8% — far above what most savings accounts pay you.
The mechanics are simpler than the panic suggests.
You owe tax as you earn income, not when you file.
If you expect to owe $1,000 or more for the year, quarterly payments are generally required.
That threshold catches a lot of people who picked up a side hustle, drove for a delivery app, or sold investments on top of a regular paycheck.
Two safe-harbor rules keep most people out of trouble.
Pay at least 90% of your current year's tax bill, or 100% of last year's — 110% if your adjusted gross income topped $150,000.
Hit either target and the penalty disappears, even if you still owe a lump sum in April.
The easiest shortcut is the annualized income method, but it requires extra paperwork most people skip.
A cleaner move: take last year's total tax from your return, divide by four, and send that each quarter.
It's not precise, but it's safe and it stops the bleeding.
You can bump up withholding on your W-2 job to cover freelance income, and the IRS treats withholding as paid evenly across the year — even if you cram it into December.
That single trick erases underpayment penalties for a lot of dual-income households.
Where people get burned is the surprise year.
A big freelance contract, a Roth conversion, or a brokerage windfall can spike your liability fast.
If you owe more than $1,000 at filing and didn't pay quarterly, expect a bill on top of the bill.
Use IRS Direct Pay, create an account through IRS Online Account, or mail a check with Form 1040-ES.
Set a calendar reminder for the remaining 2025 dates: September 15 and January 15, 2026.
One number worth knowing: the average individual penalty runs a few hundred dollars, but it scales with how much you underpaid and how long you waited.
For a freelancer netting $80,000, skipping all four quarters can mean a four-figure hit by April.
The fix isn't complicated, but it demands a little discipline now instead of a painful surprise later.
Estimate high, pay on time, and adjust in January once your real numbers are clear. **Our take:** Quarterly taxes are the least glamorous part of self-employment, which is exactly why so many people ignore them until the penalty shows up.
Final Thoughts
Treating each due date like a non-negotiable bill — not a suggestion — is the cheapest financial advice a freelancer can follow this year.