How do I avoid underpayment penalties on estimated taxes?

The safest approach is the safe harbor method: pay at least 100% of last year's total tax liability in four equal quarterly installments (110% if your prior-year AGI exceeded $150,000). Alternatively, you can pay 90% of your current-year tax.

When are quarterly estimated tax payments due?

Estimated tax payments are due April 15, June 15, September 15, and January 15 of the following year. If a due date falls on a weekend or federal holiday, the deadline moves to the next business day.

Who needs to make estimated tax payments?

Anyone who expects to owe $1,000 or more in tax after subtracting withholding and credits. This commonly includes freelancers, self-employed individuals, landlords, and investors with significant capital gains.

business Audience: self employed 2 min read

Estimated Tax Payments for Self-Employed Filers

Avoid penalties by paying quarterly estimated taxes on self-employment income.

Last updated on February 20, 2026

If you do not have withholding, the IRS expects you to pay taxes quarterly. Missing payments can trigger penalties. For the full schedule and safe harbor examples, see quarterly estimated taxes.

Key Takeaways

Estimated taxes are typically due four times per year.
Use last year’s tax or current year projections to calculate payments.
Underpaying can create penalties even if you pay in April.

How to Calculate

Two common methods:

Safe harbor: Pay 100% of last year’s tax (110% if prior-year AGI was over $150,000).
Projected income: Estimate this year’s tax and pay in quarters.

Quarterly Taxes: Due Dates

Estimated payments (also called quarterly taxes) are usually due:

April 15
June 15
September 15
January 15 (of the following year)

If a due date falls on a weekend or holiday, it moves to the next business day.

Forms and Records

Form 1040-ES worksheets to estimate quarterly payments
Schedule C or K-1 income summaries if you are self-employed or a partner

Where to Pay

Use IRS Direct Pay, EFTPS, or your tax software. For a full list of options, see the IRS payment options guide.

Self-employment tax basics: Self-employment tax explained
Home office deduction: Home office deduction guide
Quarterly schedule: Quarterly estimated taxes
Penalty calculator: Estimated tax penalty calculator

How sharper.tax Helps

When you upload your tax return to sharper.tax, the platform analyzes your income sources and withholding to determine whether you may be at risk for underpayment penalties. It also identifies strategies that could lower your estimated tax burden going forward. Sophisticated tax planning used to require a high-end CPA --- we make it available for free.

Sources

The information above is educational and not tax advice.