If you filed Form 4868 back in April, your extended tax deadline lands on October 15. That date is days away, and it trips up a lot of retirees because of one detail: the extension gave you more time to file, not more time to pay.
An Extension Is Time to File, Not Time to Pay
The IRS is direct about this: an extension gives you until October 15 to file without a late-filing penalty, but any tax you owed was still due in April. If you didn’t pay then, interest and a late-payment penalty have been building since the original deadline.
That means October 15 is not a grace period for the bill. It is the last day to get the return in so the larger penalty stops growing.
What the Penalties Actually Look Like
There are two separate penalties. The 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% of the unpaid tax per month. When both apply, the IRS reduces the filing penalty by the 0.5% payment penalty, so the two together run about 5% per month for the first five months.
Here is a simple example. Say you owe $4,000 in tax and haven’t paid or filed. Interest is extra and not shown.
| If the return is filed… | Combined penalty | On $4,000 owed |
|---|---|---|
| By October 15 | Filing penalty avoided; payment penalty and interest continue | About 0.5% per month on the unpaid balance |
| 1 month late | 5% | $200 |
| 2 months late | 10% | $400 |
| 3 months late | 15% | $600 |
| 5 months late | 25% | $1,000 |
This is a simplified illustration that assumes none of the tax was paid on time. Your actual figure depends on what you’ve already paid and credits you qualify for.
If You Can’t Pay in Full, File Anyway
Because the filing penalty is ten times the payment penalty each month, filing on time and paying what you can is almost always better than waiting until you have the full amount. After you file, the IRS offers payment plans for the balance, including an online option for many taxpayers.
- File the return by October 15 even if you can’t pay the whole bill.
- Pay as much as you can with the return to shrink the amount that keeps accruing.
- Ask about a payment plan rather than ignoring a notice.
- If you had a good reason for missing a deadline, such as serious illness, the IRS can remove or reduce penalties for reasonable cause.
If You Are Owed a Refund
If the IRS owes you money, there is generally no failure-to-file penalty, because penalties are based on tax due. Still, filing sooner gets your money sooner, and a refund can be lost if a return stays unfiled too long. Don’t treat October 15 as optional just because you expect a refund.
Free Help for Taxpayers 60 and Older
If your paperwork is a mess, you don’t need to pay a preparer. We covered the free volunteer program in our guide to Tax Counseling for the Elderly and AARP Tax-Aide. Availability this late in the season varies by location, so call ahead.
Quick Checklist Before October 15
- Gather your 1099s, Social Security statement (SSA-1099) and any 1098 forms.
- Check whether you made estimated payments and confirm the amounts.
- File electronically if you can, since the deadline counts the day you submit.
- Pay whatever you owe, or set up a payment plan right after filing.
- Keep your confirmation number and a copy of the return.
Rules and amounts can change, so confirm the details on IRS.gov before you file.