Tax season can be stressful, and with so many moving parts — gathering documents, understanding deductions, making payments — it’s not uncommon for people to miss important deadlines. One of the most common missteps is forgetting to file an extension if you’re not ready to submit your tax return by the April deadline.
If you find yourself in this situation, don’t panic. While missing the extension deadline can have consequences, you still have options to minimize penalties and interest. In this guide, we’ll explain what happens when you forget to file an extension, the steps you should take immediately, and how to avoid bigger problems down the road.
What happens if you don’t file an extension?
When you fail to file your tax return or an extension by the due date, the IRS immediately considers your return late. Unlike filing an extension (which grants you an automatic six additional months to file), missing the deadline without an extension triggers penalties.
There are two main penalties you could face:
- Failure-to-File Penalty: This is usually the largest penalty. It’s typically 5% of the unpaid taxes for each month (or part of a month) that your return is late, up to a maximum of 25%.
- Failure-to-Pay Penalty: Even if you file an extension, if you don’t pay your taxes by the original deadline (April 15 for most taxpayers), you may still be charged 0.5% of the unpaid taxes per month, up to 25%.
These penalties can add up quickly. For example, if you owe $10,000 in taxes and file three months late without an extension, you could owe around $1,500 in penalties alone — not including interest.
Interest also accrues on unpaid taxes from the original due date until you pay in full.
Step 1: File Your Tax Return as Soon as Possible
Your first and most important step is to file your tax return immediately. The longer you wait, the more the penalties grow. Even if you’re unable to pay what you owe, filing will stop the larger failure-to-file penalty from continuing to accumulate.
You don’t need to wait to have the full payment ready — filing is separate from paying. It’s better to file and arrange a payment plan afterward than to delay filing altogether.
If you have all your necessary documents ready, file your return electronically or by mail as soon as possible. If you’re missing documents, consider filing with the information you have and amending your return later if needed.
Step 2: Pay What You Can
After filing, pay as much of your tax bill as you can, even if you cannot pay the entire amount. The failure-to-pay penalty and interest are calculated based on the amount you still owe, so reducing that balance will help minimize the additional costs.
If you can’t pay the full balance, you have a few options:
- Short-Term Payment Plan: If you can pay the full amount within 180 days, you can set up a short-term plan with the IRS online.
- Long-Term Payment Plan (Installment Agreement): If you need more time, you can apply for a monthly payment plan. You’ll pay a setup fee (unless you qualify for low-income assistance), and interest will continue to accrue until the balance is paid off.
You can apply online at the IRS website if you owe $50,000 or less in combined taxes, penalties, and interest.
Step 3: Check if You Qualify for Penalty Relief
The IRS understands that life happens, and they offer penalty relief in certain cases. You may be eligible for First-Time Penalty Abatement if:
- You have a clean filing history for the past three years (no penalties for failure to file, pay, or deposit taxes).
- You filed all required returns or filed a valid extension.
- You have paid, or arranged to pay, any taxes due.
If you meet these conditions, you can request the IRS to remove your failure-to-file and failure-to-pay penalties.
Additionally, you can request penalty relief based on reasonable cause. You must show that you exercised ordinary business care and prudence but were still unable to meet your tax obligations. Valid reasons can include:
- Serious illness or death in the immediate family
- Natural disasters (like hurricanes, floods, or fires)
- Inability to obtain necessary records
- Unavoidable absence
You’ll need to provide documentation to support your claim if you seek reasonable cause relief.
Step 4: Special Note If You’re Due a Refund
If you are owed a refund from the IRS, there’s good news: there is no penalty for filing late if you don’t owe taxes. However, you must file your tax return within three years of the original due date to claim your refund. After three years, the IRS keeps the money and you forfeit your right to the refund.
For example, if you are owed a refund for the 2023 tax year (due April 2024), you must file by April 2027 to claim it.
Even if you think you’re due a refund, it’s important to file quickly. Filing late refunds can delay processing, especially during busy times at the IRS.
Step 5: If You’re Living Abroad
If you’re a US citizen living abroad, you may have an automatic two-month extension to file (typically until June 15). However, this does not extend the time to pay. Taxes owed are still due by April 15, and interest will accrue from that date.
If you still need more time beyond June 15, you should have filed Form 4868 to extend your filing deadline to October 15. If you missed both the automatic extension and did not file Form 4868, you are in the same situation as domestic filers who missed the deadline — so it’s important to file as soon as possible.
Step 6: How to Avoid Missing Deadlines in the Future
Once you’ve addressed the immediate problem, take a few steps to make sure you never miss another tax deadline:
- Set multiple reminders well before the April 15 deadline.
- Start early. Gather your documents and meet with your tax preparer early in the year.
- Use a tax professional who can file your extension automatically if needed.
- Sign up for IRS email updates or use IRS tax deadline alerts.
- If you’re an expat, consider working with a tax firm that specializes in helping Americans abroad. They can help you stay on top of both US deadlines and any foreign tax deadlines you may have.
Forgetting to file an extension for your US taxes can feel overwhelming, but you have options. Acting quickly is the most important step. File your tax return as soon as possible, pay what you can, and look into penalty relief options.
While the IRS does impose penalties and interest, they also offer flexibility and forgiveness to taxpayers who make good-faith efforts to fix the issue. Missing a deadline is stressful, but it’s not the end of the world — especially if you address it promptly.
