fino.tools
Home/All Calculators/Quarterly Estimated Tax Calculator

Quarterly Estimated Tax Calculator

Estimate your 2026 IRS tax payments to avoid underpayment penalties.

Last updated: May 2026

S

Reviewed by Sneha Iyer, CFP

Certified Financial Planner

Specializing in wealth management and retirement planning. Sneha validates the investment projection models and compound interest algorithms used across our financial tools. All mathematical models and regulatory data points have been verified for the current 2026 fiscal period.

Fact Checked| Accuracy Verified

What are Estimated Tax Payments?

In the US, taxes are "pay-as-you-go." If you are a freelancer, contractor, or business owner (1099 income), the IRS requires you to pay taxes on your income four times a year.

These payments cover both your personal Income Tax and your Self-Employment Tax(which covers Social Security and Medicare since no employer is withholding them for you).

How to use this calculator

  1. 1
    Estimate Annual Profit — Total revenue minus all deductible business expenses.
  2. 2
    Input Prior Year Tax — Check your last tax return (Form 1040, Line 24) to calculate 'Safe Harbor' amounts.
  3. 3
    Check Result — The calculator suggests the minimum quarterly payment to avoid IRS penalties.
  4. 4
    Mark Calendars — Payments are due April 15, June 15, Sept 15, and Jan 15 of the following year.

Formula & example

Quarterly Payment = Min(90% current year tax, 110% prior year tax) / 4

Current Year Tax= Estimated Income Tax + Self-Employment Tax (15.3%)
Underpayment Penalty= Charged if you owe more than $1,000 at year-end and didn't hit safe harbor.

If your net profit is $100,000, your total tax liability (SE + Income) might be ~$25,000. If you paid $15,000 last year, your Safe Harbor requirement is ~$16,500. Your suggested quarterly payment would be $16,500 / 4 = $4,125.

Benefits

Avoid Penalties

IRS underpayment penalties can be 8% or higher annually.

Cash Flow Management

Budget for taxes throughout the year instead of a giant shock in April.

Safe Harbor Compliance

Ensure you are paying just the right amount to satisfy the IRS rules.

Use cases

Full-time Freelancers

Calculate your mandatory quarterly vouchers.

Side Hustle Income

See how much extra you need to withhold from your W-2 job to cover side gig taxes.

Frequently asked questions

What if I miss a payment?+

The IRS calculates penalties daily. It is better to pay late than not at all. You can use Form 2210 to calculate the exact penalty.

How do I actually pay?+

You can pay online via IRS Direct Pay or through the EFTPS system. No paper forms are required if paying electronically.

Related calculators

Solo 401(k) Calc

Reduce your quarterly taxes by contributing to a retirement plan.