Estimated Taxes

Quarterly Estimated Taxes Explained: Who Has to Pay, the 2026 Deadlines, and How to Calculate What You Owe

By Orion Luke · October 14, 2026 · 9 min read

If you earn a W-2 paycheck, taxes are mostly invisible: your employer withholds federal income tax, Social Security, and Medicare from every check and sends the money to the IRS for you. Come April, you file a return and either get a refund or owe a little extra.

If you are self-employed — freelancing, contracting, selling on Etsy or Gumroad, driving for a delivery app, renting out property — nobody withholds anything for you. Every dollar that lands in your account arrives with its taxes still attached. And the IRS does not wait until April to collect. It expects you to pay as you earn, in four quarterly installments called estimated taxes.

Miss them and two things happen: you can owe an underpayment penalty on top of the tax itself, and you walk into April facing a tax bill you never set money aside for. This guide covers who has to pay, the exact 2026 deadlines, how to calculate what you owe, and what happens if you skip.

Who has to pay estimated tax

The general rule for individuals: you must pay estimated tax if you expect to owe $1,000 or more in tax for the year after subtracting your withholding and refundable credits. (Corporations have a $500 threshold; this guide is for individuals.)

In practice, that means:

• Employees with only W-2 income usually don't need estimated payments — withholding covers it, as long as the withholding is roughly right.
• Self-employed people — freelancers, independent contractors, gig workers, online sellers, landlords — almost always need to pay estimated tax, because nothing is withheld from their income.
• People with mixed income (a W-2 job plus a side business) may need estimated payments on the side income, or they can increase W-2 withholding to cover it instead. Either approach satisfies the pay-as-you-earn requirement.

The $1,000 figure is the federal trigger. Some states have their own estimated-tax rules and thresholds, so check your state's requirements separately.

The 2026 quarterly deadlines

Estimated tax is paid in four installments. For the 2026 tax year, the IRS due dates are:

1. 1st quarter (January 1 – March 31, 2026): due April 15, 2026
2. 2nd quarter (April 1 – May 31, 2026): due June 15, 2026
3. 3rd quarter (June 1 – August 31, 2026): due September 15, 2026
4. 4th quarter (September 1 – December 31, 2026): due January 15, 2027

A few things to notice. First, the "quarters" are not calendar quarters — the second period is only two months (April and May), and the fourth stretches four months (September through December). Second, the fourth payment for 2026 is due in January 2027, but it still counts toward your 2026 tax year. Third, when a due date falls on a weekend or federal holiday, it shifts to the next business day — always verify the current year's dates against IRS guidance before you pay.

Each payment covers the income you earned in that period. You are not supposed to guess your whole year in January and divide by four (though there is a legal shortcut for that — the safe harbor rule, covered in its own guide). The standard method is pay-as-you-go: estimate each period's income, calculate the tax on it, and pay.

How to calculate what you owe each quarter

Calculating estimated tax means answering three questions: what did I earn, what do I get to subtract, and what tax applies to the rest.

Step 1: Figure out your net self-employment income for the period

Start with gross receipts — everything clients and platforms paid you — and subtract your ordinary and necessary business expenses. The result is your net profit (also called net earnings from self-employment). Track this per period, not just annually, because each quarterly payment is based on that period's income.

Example: in Q1 you billed $24,000 and spent $3,000 on software, supplies, and a contractor. Your Q1 net profit is $21,000.

Step 2: Calculate self-employment tax

Self-employment tax is 15.3% — 12.4% for Social Security plus 2.9% for Medicare — applied to 92.35% of your net earnings. (The 92.35% factor exists because employees effectively split payroll tax with their employer; the factor approximates the employer half you don't pay as your own employer.)

On the $21,000 Q1 net profit: $21,000 × 0.9235 = $19,393.50 in taxable self-employment earnings. × 0.153 = $2,967.21 in self-employment tax for the quarter.

Note: the Social Security portion (12.4%) only applies up to the annual Social Security wage base — $184,500 for 2026. The Medicare portion (2.9%) has no cap, and there's an additional 0.9% Medicare tax on earnings above $200,000 (single) or $250,000 (married filing jointly). High earners should account for all three layers.

Step 3: Calculate federal income tax

Your net profit also counts toward federal income tax, but not dollar-for-dollar:

• Subtract one-half of your self-employment tax — that's an above-the-line deduction everyone with SE income gets.
• Subtract the standard deduction ($16,100 for single filers in 2026; higher for married filing jointly or head of household) or your itemized deductions, whichever is larger.
• Apply the 2026 federal income tax brackets to what's left. Brackets are marginal — only the income inside each bracket is taxed at that bracket's rate.

Continuing the example: half of the $2,967.21 SE tax is $1,483.61. Annualize roughly (this is one quarter, so multiply by four for a full-year illustration): $84,000 net profit, $11,868.84 SE tax, half = $5,934.42 deductible. $84,000 − $5,934.42 − $16,100 standard deduction = $61,965.58 in taxable income, taxed at 2026 marginal rates. (Check the current IRS tax tables for the exact bracket math — rates and thresholds are set annually.)

Step 4: Add state estimated tax

Most states with an income tax also expect quarterly estimated payments. The calculation varies by state — many people use a flat percentage of net income as a reserve and true it up at filing time. Treat the state figure as a reserve, not a filing number, and verify your state's rules.

Step 5: Pay

You can pay online at IRS Direct Pay or through the Electronic Federal Tax Payment System (EFTPS), by mail with Form 1040-ES vouchers, or through the IRS2Go app. Keep confirmation numbers — you'll need them at filing time, and they're your proof if a payment ever goes missing.

What happens if you skip quarterly payments

Two consequences, one certain and one conditional.

The certain one: the April bill. If you never made estimated payments, your entire year's tax comes due with your return. For a freelancer with $60,000 in net profit, that can easily be a five-figure check written in one sitting — for money that felt like spending money all year. This is the "April shock," and it's the most common tax disaster in self-employment.

The conditional one: the underpayment penalty. The IRS can charge a penalty when you underpay during the year. It's calculated like interest on the amount you should have paid each quarter, at a rate the IRS sets quarterly — so it moves with interest rates. The penalty is avoidable: if you paid enough through withholding and timely estimated payments to meet the safe harbor thresholds (90% of the current year's tax, or 100% of last year's tax — 110% if your prior-year adjusted gross income was over $150,000), no underpayment penalty applies even if you still owe a balance in April. There's a full guide to the safe harbor rule on this site.

One more wrinkle: the penalty is figured per quarter. Paying the full year late in January doesn't erase penalties for the earlier quarters you skipped. Timing matters, not just the total.

A simple system that prevents all of this

The math above is straightforward but tedious to redo every quarter — which is exactly why most freelancers don't do it, and exactly why the April shock keeps happening. The fix is a system, not willpower:

1. Know your reserve rate. Your combined effective tax rate (SE tax + income tax + state, divided by net profit) tells you what percentage of every payment belongs to the IRS. Move that percentage to a separate savings account the moment money lands.
2. Recalculate quarterly. Re-run the estimate on actual year-to-date profit each quarter — not on a guess you made in January.
3. Pay on the deadlines. April 15, June 15, September 15, January 15. Put them on your calendar now.

Do those three things and estimated tax becomes a routine instead of a crisis.

General information only — not tax advice. Tax law changes; verify figures against current IRS guidance and consult a tax professional for your situation.