Quarterly Estimated Taxes: A Guide for Freelancers and Self-Employed Professionals

If you've recently gone freelance, started a side business, or made any transition away from traditional W-2 employment, you may have encountered a concept that trips up a lot of first-timers: quarterly estimated taxes. The IRS expects most self-employed individuals and business owners to pay their taxes throughout the year — not all at once in April. Miss those payments, and you'll face penalties on top of the balance you already owe.

Here's what you need to know.

Why Quarterly Estimated Taxes Exist

The U.S. tax system is a pay-as-you-go system. When you're employed and receive a W-2, your employer withholds taxes from every paycheck and remits them to the IRS on your behalf. You may not think about it, but your tax bill is being paid in small installments all year long. When you're self-employed, there's no employer doing that for you — so the IRS requires you to do it yourself, four times a year.

This isn't a burden unique to freelancers — it applies to sole proprietors, LLC owners, partners in a partnership, S-Corp shareholders who pay themselves distributions beyond their salary, and anyone else whose income isn't subject to automatic withholding.

The Quarterly Due Dates

Estimated tax payments are due four times a year. The standard due dates are April 15th (for income earned January–March), June 15th (April–May), September 15th (June–August), and January 15th of the following year (September–December). When a due date falls on a weekend or holiday, the deadline shifts to the next business day. Missing these dates — even by a few days — can trigger underpayment penalties.

How Much Should You Pay?

There are two safe harbor methods for calculating estimated payments. The first is to pay at least 90% of your current year's tax liability across your four installments. The second — and often more practical — approach is to pay 100% of last year's tax liability (or 110% if your adjusted gross income exceeded $150,000). If you pay either amount across the four quarters, you won't owe underpayment penalties, even if your actual liability turns out to be higher.

The 100% of prior year liability approach is especially useful in years when your income is hard to predict — like a year you're launching a new business or transitioning between income sources.

Don't Forget Self-Employment Tax

One thing that surprises many first-time self-employed taxpayers: in addition to federal income tax, you also owe self-employment tax on your net earnings. Self-employment tax covers Social Security and Medicare — the equivalent of what would have been split between you and your employer if you were on payroll. The combined rate is 15.3% on the first $160,200 of net earnings (as of recent years) and 2.9% beyond that. This is on top of your regular income tax rate.

When estimating how much to set aside from each payment, budget for both. A common rule of thumb is to set aside 25–30% of every dollar of net self-employment income — though the right number depends on your income level, deductions, and filing status.

The Practical Step: Work With a CPA

The best way to handle estimated taxes is to work through your projections with a CPA at the start of the year — and revisit them if your income changes significantly. This prevents both underpayment (which causes penalties) and overpayment (which is essentially an interest-free loan to the government). Getting these numbers right isn't complicated when you have accurate books and someone who's paying attention — and it's one of the clearest ways a good CPA pays for themselves.