If you can’t pay your taxes by Wednesday, the worst move is the one that feels most natural: leaving the return in a drawer until you have the money. The IRS penalty for not filing runs 5% of the unpaid tax every month. The penalty for not paying is 0.5%. That’s ten times the damage on the same debt, and the only difference is whether a form reached the IRS on time.
The IRS said as much on April 9 in its last-minute filing reminder (IR-2026-47), urging people to file and pay what they can even if they can’t cover the full bill. That release also repeats the line people miss every year: an extension of time to file is not an extension of time to pay. Below is what each choice costs on a $6,000 balance, including the option a lot of people grab first: putting the whole bill on a credit card.
Not filing is the expensive mistake, not owing
The IRS failure-to-file penalty is 5% of the unpaid tax for each month or partial month the return is late, capped at 25%. The failure-to-pay penalty is 0.5% a month, also capped at 25%. When both apply in the same month, the IRS reduces the filing penalty by the payment penalty, so you pay 4.5% plus 0.5%, or 5% combined. On a $6,000 balance that’s $300 a month for being late with the paperwork versus $30 a month for being late with the money.
There’s also a floor that hits small balances hard. If a return due in 2026 is more than 60 days late, the minimum failure-to-file penalty is $525 or 100% of the tax owed, whichever is less. Say you owe $800 and file three months late. The normal math says 4.5% times three months, or $108. The minimum overrides it, and you pay $525, which is 65.6% of what you owed in the first place. The popular explainers on missed deadlines rarely spell out that floor, and it’s the part that turns a small tax bill into a large one.
Filing on time also earns you a discount. The failure-to-pay penalty drops to 0.25% a month while an approved installment agreement is in effect, but only if you filed on time. Skip the return and you get hit with the 5% penalty and lose the 0.25% rate.
An extension buys time to file, not time to pay
Form 4868 moves your filing deadline to October 15. It does nothing to the payment deadline, which is still April 15. Interest starts on any unpaid balance the day after the deadline, and the 0.5% monthly penalty does too. The extension’s real value is that it shuts off the 5% penalty while you gather documents, as long as you file by October. If you already know what you owe and simply can’t pay it, an extension mostly delays the paperwork you’d need for a payment plan anyway.
The interest piece is modest right now. The IRS rate on individual underpayments is 6% for April through June 2026, down from 7% in the first quarter, compounded daily. The rate resets every quarter, so the numbers below assume it stays at 6%, which nobody can promise.
What an IRS payment plan actually costs
The IRS payment plans page lays out the fees. A short-term plan, meaning you pay in full within 180 days, has no setup fee if you owe less than $100,000 combined. A long-term monthly plan costs $29 to set up online with direct debit from your checking account, or $69 online if you’d rather send payments yourself. Apply by phone, mail or in person and those jump to $107 and $178. Low-income filers get the direct debit fee waived. Penalties and interest keep running on either plan until the balance hits zero.
Say you owe $6,000 on April 15, you file on time, and you set up a 12-month plan online with direct debit. With 6% interest compounded daily, the 0.25% monthly penalty and the $29 fee, a fixed payment of $524.31 clears it in a year. Over that year you pay $198.20 in interest and $93.49 in penalties, and with the $29 fee the total cost comes to $320.69.
If you can swing a bigger payment, the short-term plan is cheaper. Paying $1,034.76 a month clears the $6,000 in six months. I’ve assumed the full 0.5% penalty applies, since the reduced rate is tied to an installment agreement. Even so, the total is $102.39 in penalties and $106.15 in interest, or $208.54, with no setup fee. Roughly speaking, a long-term plan costs about 9% a year (6% interest plus 0.25% times 12 months) and a short-term plan about 12%, but you’re on the hook for less time.
Putting your tax bill on a credit card costs more than twice as much
Paying the IRS by card means going through a private processor that adds a fee: 1.75% at Pay1040 and 1.85% at ACI Payments, the two card processors the IRS lists. On $6,000 that’s $105 or $111 before any interest.
Then there’s the APR. The Federal Reserve’s G.19 consumer credit release from April 7 puts the average rate on credit card accounts that paid interest at 21.52% in February 2026. That’s the number that matters for anyone who can’t pay the balance off right away, which is everyone in this situation by definition.
| $6,000 owed April 15, 2026 | Monthly payment | Interest | Penalties and fees | Total cost |
|---|---|---|---|---|
| IRS long-term plan, 12 months | $524.31 | $198.20 | $122.49 | $320.69 |
| IRS short-term plan, 6 months | $1,034.76 | $106.15 | $102.39 | $208.54 |
| Credit card via Pay1040, 12 months | $569.98 | $734.81 | $105.00 | $839.81 |
| Don’t file or pay until Oct. 15 | none | $182.71 | $1,530.00 | $1,712.71 |
The card row works like this: charge $6,000 plus the $105 fee, then pay it off in 12 equal payments of $569.98 at 21.52%. Interest comes to $734.81, so the total cost is $839.81, which is $519.12 more than the IRS plan. Use ACI instead and the total is $846.53. The bottom row is the person who neither files nor pays until October 15 without an extension: five months at the combined 5% plus a sixth month at 0.5% adds up to $1,530 in penalties, and $182.71 of interest on the tax alone brings it to $1,712.71. File on time and pay that same October day, and the cost drops to $362.71.
A card only wins in a narrow case: you have a 0% intro APR that lasts long enough to clear the balance, or you’re paying off the full statement within a month and the rewards beat the 1.75% fee. If neither is true, you’re swapping a 9% IRS loan for a 21.52% bank loan and paying a fee for the privilege. I’d skip it.
The IRS is a patient lender if you file
A lot of people panic about owing the IRS and borrow at card rates to make the debt vanish. That’s backwards. Once you’ve filed, the IRS charges 6% interest plus a 0.25% monthly penalty, and the agency says most online applicants hear right away whether their plan is approved. A card charges more than twice that, and the balance pushes up your credit utilization until it’s gone. Americans already owed $1,327.6 billion in revolving credit in February 2026, according to the same Fed release. Moving a tax bill onto that pile at 21.52% buys you nothing the IRS wasn’t already offering for less.
If you have other debts in the mix, the order matters too. Our piece on the pros and cons of early debt payoff covers how to rank balances by rate, and an IRS plan at roughly 9% usually ranks below a card. Before you assume the bill is final, check whether you missed anything on the return itself. Our list of commonly overlooked tax deductions is a quick scan.
What to do before Wednesday if you can’t pay your taxes
File your return by April 15, even with a balance due. Pay whatever you can with it, because every dollar paid now stops accruing both interest and penalties. Then go to the IRS online payment plan tool and pick the shortest plan whose monthly payment you can actually make. If six months works, the short-term plan is free to set up; if you need longer, choose direct debit and apply online to keep the fee at $29.
If you can’t pay your taxes, you have a cash-flow problem with a cheap fix. If you don’t file, you have a penalty problem with a 25% ceiling and a $525 floor. Penalty relief, hardship options and plan eligibility depend on your situation, so a tax professional can confirm what applies to you.
Sources: IRS, IRS, Federal Reserve, IRS
