10 Important Things to Know About US Tax Deadlines

As tax season approaches, understanding key tax deadlines can be crucial for keeping your finances on track. While most of us know that taxes are due in April, it’s easy to overlook other essential dates and requirements, especially if you’re a business owner, freelancer, or expatriate. In this guide, we’ll break down ten critical U.S. tax deadlines, explaining what each date means and why it’s important to stay informed. By the end, you’ll have a clearer picture of how to manage your tax obligations effectively and avoid unnecessary penalties. 

1. Main Tax Filing Deadline: April 15 

For most individual taxpayers, the federal tax return is due on April 15 each year. Missing this date without filing an extension can lead to penalties and interest on any unpaid taxes. However, if April 15 falls on a weekend or holiday, the deadline moves to the next business day. 

For 2025, the tax filing deadline is scheduled for Monday, April 15. Failing to file by this date could result in a failure-to-file penalty of 5% of unpaid taxes for each month the return is late. 

Filing by April 15 allows you to avoid the IRS late-filing penalty, which can be 5% of the unpaid taxes for each month the return is late, up to 25% of the unpaid amount. It also helps you avoid interest that accrues daily on any unpaid tax balance after the deadline. This deadline is crucial for both individual taxpayers and business owners who need to report their income accurately to avoid legal and financial repercussions. 

2. Requesting an Extension 

If you need more time to file, you can request an extension using Form 4868. This form must be filed by April 15, and it grants an automatic six-month extension, giving you until October 15 to submit your return. Remember, this extension only applies to the filing, not to paying any taxes owed. Therefore, you’ll need to estimate and pay what you owe to avoid penalties. 

Steps to Request an Extension 

Complete Form 4868: Available on the IRS website or through tax software. 

Submit Online: Use e-filing services or IRS Direct Pay to submit your extension. 

Pay Estimated Tax Due: If you expect to owe taxes, send an estimated payment to avoid interest charges. 

The IRS advises that extensions must be filed by the April deadline to avoid late filing fees. For those who travel frequently or have complex financial situations, an extension can be a vital tool to ensure accuracy and avoid errors on your tax return. 

3. Quarterly Estimated Tax Deadlines 

If you’re self-employed, a freelancer, or earn income that isn’t subject to withholding, you must make quarterly estimated tax payments. The IRS requires these to cover your Social Security, Medicare, and income taxes. The dates are: 

Failing to make these payments can result in underpayment penalties, so it’s crucial to pay on time. You can calculate your estimated taxes using Form 1040-ES. Estimated tax payments are required if you expect to owe at least $1,000 in taxes for the year beyond withholding and credits. 

Real-World Scenario 

Freelancers often have fluctuating incomes, which can make estimating taxes a bit tricky. If you work in an industry with seasonal income, you might earn more in some quarters than others. The IRS allows you to adjust your quarterly payments based on actual earnings, which can help prevent overpayment and ensure you’re in line with IRS requirements. 

4. Business Tax Deadlines 

If you own a business, your filing deadlines may vary depending on its structure: 

Partnerships & S Corporations: Due on March 15. These entities can file for a six-month extension, moving the due date to September 15. 

C Corporations: Due on April 15 (for calendar-year corporations). Corporations can also file Form 7004 to extend their filing deadline to October 15. 

Additionally, businesses classified as limited liability companies (LLCs) can also be subject to these deadlines depending on how they’re taxed, so it’s essential to know your business classification. 

Example:

Let’s say your business is an S corporation. You’d need to file your return (or request an extension) by March 15 to avoid penalties. If you miss this deadline and owe taxes, you may incur a late payment penalty of 0.5% of the unpaid tax balance for each month it’s overdue. This can be avoided by filing early and paying any estimated taxes due by the deadline. 

5. Deadlines for Expatriates 

U.S. citizens and resident aliens living and working outside the U.S. get an automatic two-month extension to June 15 to file their federal income tax returns. This applies whether you’re stationed overseas temporarily or reside abroad year-round. However, if you owe taxes, interest still accrues from April 15. 

Additional Extensions for Expatriates 

Expatriates can also file Form 2350 to request additional time beyond June 15, particularly if they expect to meet certain residence or physical presence requirements. Many expatriates file with the Foreign Earned Income Exclusion (Form 2555), allowing them to exclude a portion of their earned income from U.S. taxation. In 2023, this amount was $112,000, and adjustments for inflation are made each year. 

For those working abroad in high-tax countries, using the Foreign Tax Credit (Form 1116) may also help reduce double-taxation issues by offsetting U.S. taxes with foreign taxes paid. 

6. State-Specific Deadlines 

In addition to federal deadlines, each state has its own filing requirements. For instance, California and New York typically align with the federal April 15 deadline. However, states like Massachusetts and Maine may have deadlines that vary slightly based on state holidays. 

Checking your state’s Department of Revenue website can ensure you’re compliant with both federal and state filing requirements. It’s also worth noting that some states, like Texas, Florida, and Washington, do not have a state income tax. 

7. IRA, SEP IRA, and HSA Contribution Deadlines 

If you contribute to an Individual Retirement Account (IRA), a Simplified Employee Pension (SEP) IRA, or a Health Savings Account (HSA), you can make contributions for the previous year up until the April 15 tax filing deadline. These contributions can reduce your taxable income, so contributing by the deadline can be financially advantageous. 

For SEP IRAs, if you have an extension, you can contribute up until your extended deadline, usually October 15. Contributions to these accounts can result in significant tax savings. For 2023, the IRA contribution limit was $6,500 for those under 50, with an additional $1,000 catch-up contribution allowed for those 50 and older. 

Pro Tip: 

Maximizing your contributions can not only reduce taxable income but also help secure your financial future. For example, HSA contributions are a great way to save for healthcare expenses while getting a tax deduction, as they’re one of the few accounts that offer tax-free contributions, growth, and withdrawals when used for qualified medical expenses. 

8. Disaster Relief Extensions 

In cases of federally declared disasters, the IRS often extends filing deadlines for affected individuals and businesses. This includes additional time to file returns, pay taxes, and make other time-sensitive payments. 

For example, the IRS extended deadlines for taxpayers in certain disaster areas following recent hurricanes and wildfires. Check the IRS Disaster Relief page regularly if you live in an area prone to natural disasters. Following the 2023 wildfires in California, affected individuals received extensions on their 2022 tax filings and payments until October 16, 2023. 

9. Self-Employment and Solo 401(k) Contributions 

If you’re self-employed, you can contribute to retirement accounts like a Solo 401(k) until the tax filing deadline, including any extensions. This contribution can be made until October 15 if you’ve filed for an extension. This allows you to increase retirement savings while potentially reducing taxable income. Self-employed taxpayers are also eligible to deduct their contributions to these accounts, up to 25% of their net earnings. 

10. Consequences of Missing Deadlines 

Missing tax deadlines can result in several penalties and fees. The Failure-to-File Penalty is typically 5% of the unpaid taxes for each month your return is late, up to 25%. The Failure-to-Pay Penalty is 0.5% of the unpaid taxes per month. The IRS also charges interest on unpaid balances, which compound daily. 

Late Payment Interest Rates 

For 2023, the IRS interest rate for underpayment of taxes was 7% per year, compounded daily. This rate can vary based on federal interest rate adjustments, so the impact of missing deadlines can become substantial over time. 

Staying Ahead of Tax Deadlines 

Staying informed about tax deadlines is essential for any taxpayer. By understanding these ten critical dates and taking proactive steps to meet them, you can avoid costly penalties, reduce stress, and feel more confident managing your tax obligations. Consider setting calendar reminders, working with a tax professional, or using tax software to stay on top of deadlines. With a little preparation, you’ll have a smoother tax season and can focus on what matters most to you. 

For business owners, keeping track of both federal and state deadlines can be challenging, so investing in a tax advisory service may be a smart choice. Meanwhile, expatriates should make use of available resources to stay compliant with U.S. tax laws. Whatever your situation, having a solid understanding of tax deadlines is key to staying in good standing with the IRS. 

FAQs 

1. When are taxes due? 

Most people need to file their taxes by April 15. If April 15 is on a weekend or holiday, then the deadline is the next business day. 

2. What if I need more time to file my taxes? 

You can ask the IRS for extra time to file by submitting a Form 4868 before April 15. This gives you six more months, until October 15, to file your tax return. 

3. Who needs to pay taxes every three months? 

People who are self-employed or earn income that isn’t from a regular paycheck, like freelancers, usually need to pay taxes four times a year. These payments are due in April, June, September, and January. 

4. Are there different deadlines for businesses? 

Yes, businesses like partnerships and S corporations need to file taxes by March 15, not April 15. They can also get a six-month extension if needed. 

5. What happens if I miss the tax deadline? 

If you miss a deadline, the IRS might charge a penalty and interest on any unpaid taxes. This means you may have to pay extra, so it’s best to file on time to avoid extra fees.