Quarterly Estimated Tax Calculator 2026

How Quarterly Estimated Taxes Work in 2026

If you're self-employed, a freelancer, or an independent contractor, the IRS expects you to pay taxes throughout the year — not just at filing time. Since no employer withholds taxes from your 1099 income, you're required to make quarterly estimated tax payments using Form 1040-ES. These payments cover your self-employment tax (Social Security + Medicare), federal income tax, and state income tax.

2026 Quarterly Due Dates

The IRS divides the tax year into four payment periods, each with its own deadline. Note that the periods aren't equal — Q2 covers only two months while Q3 covers three.

Safe Harbor Rules: How to Avoid Penalties

The IRS won't charge an underpayment penalty if you meet one of these safe harbor thresholds through your quarterly payments and any withholding: pay at least 90% of your current-year tax liability, or pay 100% of your prior-year tax liability (110% if your prior-year AGI exceeded $150,000, or $75,000 if married filing separately). Many self-employed workers use the prior-year method because it gives them a fixed target they can calculate in advance.

Who Needs to Pay Quarterly Estimated Taxes?

Generally, you must make quarterly payments if you expect to owe $1,000 or more in federal tax after subtracting withholding and credits. This applies to freelancers, independent contractors, gig workers, sole proprietors, partners, and S-Corp shareholders. If you also have a W-2 job, you may be able to increase your withholding to cover your self-employment tax instead of making separate quarterly payments.

Underpayment Penalty

If you don't pay enough through quarterly payments or withholding, the IRS charges an underpayment penalty based on the federal short-term rate plus 3 percentage points. For 2026, this rate is approximately 8% annually. The penalty is calculated on the underpaid amount for each quarter, from the due date until the payment is made or April 15 of the following year.