08/28/2026
If I owe, I’ll just pay it at tax time.”
That may sound like a plan—but it also means you could be using the IRS as a lender.
For the fourth quarter of 2026, the IRS underpayment interest rate is 7%. If you still have a balance after the tax deadline, penalties and other fees can increase the cost even more.
The IRS may start at 7%, but that may not be your final cost.
Before holding on to money that should be set aside for taxes, consider what that cash is actually doing for your business. Is it producing a return that justifies the cost—or is it simply being spent elsewhere?
Waiting to pay isn’t automatically a bad decision. But it should be an informed financing decision, not a surprise at tax time.