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Quarterly Estimated Taxes: A Complete Guide for Self-Employed Workers

WriteOff TeamMarch 9, 20264 min read

Reviewed September 2026 for tax years 2025–2026. Dollar amounts are labeled by tax year; confirm current figures at IRS.gov before filing. This article is general information, not tax advice.

Unlike W-2 employees who have taxes withheld from every paycheck, freelancers are responsible for paying their own taxes throughout the year. The IRS expects quarterly payments using Form 1040-ES, and underpaying means penalties and interest on top of your tax bill.

Who Needs to Pay Estimated Taxes?

The IRS generally requires quarterly payments if both of the following are true:

  1. You expect to owe $1,000 or more in federal tax after subtracting withholding and refundable credits.
  2. Your withholding and credits will cover less than the smaller of 90% of this year's tax liability or 100% of last year's tax liability (110% if your AGI exceeded $150,000).

If you had self-employment income and not enough withheld from a W-2 job to cover the resulting tax, you almost certainly need to make quarterly payments.

The Four Due Dates

Quarterly tax payments follow a slightly uneven schedule:

Payment Period Due Date
January 1 - March 31 April 15
April 1 - May 31 June 15
June 1 - August 31 September 15
September 1 - December 31 January 15 (following year)

If a due date falls on a weekend or holiday, the deadline moves to the next business day. For tax year 2026, none of the dates shift: April 15, June 15 and September 15, 2026, and January 15, 2027. (For 2025, the second payment was due June 16 because June 15, 2025 was a Sunday. For 2027, expect the final payment to fall on January 18, 2028, since January 15 is a Saturday and January 17 is a federal holiday - confirm with the 2027 Form 1040-ES.)

Mark these dates now. Missing even one payment triggers a penalty calculated from the due date until payment is received.

How to Calculate Your Estimated Tax

Two main approaches:

Method 1: Current-Year Estimate

Estimate your total income, deductions, and credits for the year, then calculate the tax owed. Divide by four for your quarterly amount. The IRS provides a worksheet in the Form 1040-ES instructions for this.

For self-employment income, include:

  • Federal income tax on your net profit
  • Self-employment tax (15.3% on net earnings up to the Social Security wage base - $176,100 for 2025, $184,500 for 2026 - then 2.9% above that)

Method 2: Safe Harbor

If your income is unpredictable, use safe harbor. Pay at least 100% of last year's total tax liability, divided into four equal payments. If your AGI was over $150,000 last year ($75,000 if married filing separately), the threshold increases to 110%.

This guarantees no underpayment penalty regardless of how much you actually earn.

Underpayment Penalties

If you do not pay enough by each quarterly due date, the IRS charges an underpayment penalty based on the federal short-term interest rate plus 3 percentage points, calculated separately for each quarter.

You can avoid the penalty if:

  • You owe less than $1,000 after subtracting withholding and credits
  • You paid at least 90% of the current year's tax liability
  • You paid at least 100% (or 110%) of the prior year's tax liability

Use Form 2210 to calculate the penalty or request a waiver for uneven income patterns.

State Estimated Taxes

Most states with an income tax also require quarterly estimated payments on a similar schedule. Common examples:

  • California: Same federal due dates; 30% due with Q1, 40% with Q2, 0% with Q3, 30% with Q4
  • New York: Standard 25% per quarter
  • Texas, Florida, Nevada, Washington: No state income tax, no state estimated payments

Check your state's franchise tax board or department of revenue for specific rules.

How to Make Payments

Options for paying federal estimated taxes:

  • IRS Direct Pay (irs.gov/directpay) - Free bank transfer
  • EFTPS (Electronic Federal Tax Payment System) - Free, must enroll in advance
  • Credit/debit card - Third-party processor; small fee applies
  • Check or money order - Mail with a Form 1040-ES voucher

When paying online, select "Estimated Tax" and choose the correct tax year and quarter.

Tips for Managing Quarterly Payments

Set aside money after every payment you receive. Move 25-30% of each freelance payment into a separate savings account for taxes.

Adjust as you go. If income changes significantly, recalculate your payments. You are not locked into equal quarterly amounts. The annualized installment method on Form 2210 lets you pay based on when you actually earned the income.

Track deductions in real-time. Every deductible expense reduces your taxable income and your quarterly payment. The more deductions you track during the year, the more accurate your estimates.


The Takeaway

Quarterly estimated taxes are not intuitive, but they are not optional. The key is a system: know your due dates, calculate based on real numbers, and track deductions as you earn.


Sources

Safe harbor: pay 100% of prior year tax (110% if prior year AGI > $150,000), OR 90% of current year tax. Q2 covers April-May only (not April-June). Source: IRC § 6654.

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