On Extension: Can You Still Contribute to an IRA, HSA, or SEP? If Not Now, When?

Smart Moves in the Filing Gap 

Filing an extension can buy you time, but not as much as you think. 

Many taxpayers assume that filing for a six-month extension also pushes back their deadline to contribute to retirement or health accounts. Unfortunately, that’s not true for most plans. If you’re holding out hope to still fund an IRA or HSA for 2024, you may be too late. But if you’re a small business owner or self-employed Montanan, there’s still a powerful opportunity. 

Here’s a Montana-grounded look at what’s still possible — and what deadlines you’ve already missed. 

What the Extension Does (and Doesn’t) Give You 

When you file a federal tax extension (Form 4868), you get six more months to file your return, typically moving your due date from April 15 to October 15. But it’s just that: extra time to file, not to contribute, pay, or plan after the fact. 

📌 Montana automatically honors federal extensions, so you don’t need to file a separate form with the state. 

That said, knowing which contributions are still allowed — and how they affect your federal and Montana returns — can help you make the most of the time you have left. 

IRAs and HSAs: April Deadlines Are Final 

Traditional & Roth IRAs 

• Contribution deadline: April 15, 2025 (for tax year 2024) 

• Extension? No 

• Limit: $7,000 ($8,000 if 50+) 

Even if you’re on an extension, IRA contributions have** to be made by Tax Day**. No exceptions. 

This applies to both Traditional IRAs (which may be deductible) and Roth IRAs (funded with after-tax dollars). If you didn’t make your 2024 contribution by April 15, you’ve missed it. 

HSAs (Health Savings Accounts) 

Contribution deadline: April 15, 2025 Extension? No Limit: $4,150 individual / $8,300 family (+$1,000 if 55+) 

Health Savings Accounts follow the same rule — no contribution after April 15 for the prior tax year, even if your tax return is still pending. 

🧠 Montana note: Since Montana uses your federal adjusted gross income (AGI) as a starting point, missed IRA or HSA deductions also mean a higher state tax bill. 

SEP IRAs: Your Last-Minute Hero 

Now for the good news. 

If you're self-employed, run a business, or work in agriculture or contracting — and you've filed an extension — the SEP IRA is your best (and only) remaining play. 

SEP IRA Contributions 

• Contribution deadline: October 15, 2025 (with valid extension) 

• Extension? ✅ Yes 

• Limit: Up to 25% of compensation or $69,000 for 2024 

This means you still have time to: 

• Open a SEP IRA (if you haven’t yet) 

• Fund it 

• Deduct it on your 2024 return 

📌 Montana insight: For many in construction, ag, and consulting, this strategy can cut federal and state taxes, potentially freeing up thousands in liability. And SEP plans have no employee match requirement unless you choose to contribute for others. 

What About SIMPLE IRAs, Solo 401(k)s, and Other Plans? 

Most follow plan-specific rules and must be established by year-end (Dec 31) to allow prior-year contributions. If you didn’t have one in place last year, it’s likely too late to fund for 2024, but you can still plan for 2025. 

If you’re considering these for your Montana business, we can help compare options and filing requirements before year-end. 

🧾 Final Cheat Sheet 

Swanson Agency Takeaway: 

Plan Late — But Not Too Late 

If you’re sitting on a valid tax extension and some extra cash, your SEP IRA could be the last significant move to reduce your tax bill for 2024. But don’t wait until October — banks and custodians often have processing delays, and the IRS doesn’t accept “I meant to” as a deduction. 

For Montana’s contractors, consultants, and independent professionals, this might be the best remaining tax lever you can still pull. 

Swanson Agency Montana Roots. Future Focused. 

Tax clarity, business strategy, and planning support — for every season. 

📍 Need help setting up or funding a SEP before the deadline? Let’s talk.