IRS penalty and interest calculator

See how fast an unpaid IRS balance grows

Move the sliders, or type exact numbers, to estimate what an unpaid federal tax bill becomes after penalties and daily interest.

Original tax owed

Type any amount up to $10,000,000.

Time since it was due

months

Was the return filed on time?

Not filing adds a penalty of up to 25% on top of the late-payment penalty.

IRS interest rate

7% is the IRS rate for Q4 2026, compounded daily. The IRS resets it every quarter.

Estimated balance now

Growing by about

Added since you opened this page: $0.00

Original tax

Penalties

Interest

Tax Penalties Interest Today. Beyond it, if nothing changes

Free, confidential review

Talk to a tax professional about your estimate

A credentialed tax professional from Secure Tax Experts, LLC will look at your situation and explain which IRS options could slow or stop this growth. The review is free.

Your estimate, sent with this formUpdates as you change the calculator

First name

Last name

Mobile phone

Email optional

State you live in

Who owes the IRS?

What is your biggest concern right now?

How many tax years are unpaid?

Best time to call

Anything else we should know? optional Please don't include your Social Security number or bank details.

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See how fast an unpaid IRS balance grows

Talk to a tax professional about your estimate

Every month adds penalties and interest