If you’re a small business owner who filed a tax extension earlier this year, it’s crunch time to finish your return. But there’s no need to stress — you still have time to file your business tax return before the extension deadline, and TaxAct® can help you get there.
Whatever your situation (maybe you run a sole proprietorship, manage a team under an S corporation, or operate as part of a partnership), it’s important to know precisely which tax forms you need, your tax year filing due date, and what tax deductions are available. TaxAct Business can help you with all of this and more.
Even if you used a different provider to submit your business tax extension, you can still finish filing your federal income tax return with TaxAct — and avoid last-minute stress and potential IRS penalties. Let’s get into it.
When are business taxes due in 2025 if you filed an extension?
The extension deadline for most calendar-year business entities that filed an automatic extension of time to file depends on the type of business you run:
| Business type | Original business tax return deadline | Extension request form | Extended due date |
| Sole proprietorship (filing Schedule C with an individual income tax return) | April 15, 2025 | Form 4868 | Oct. 15, 2025 |
| Partnership or LLCs taxed as partnerships | March 17, 2025 | Form 7004 | Sept. 15, 2025 |
| S corporations (S corps) | March 17, 2025 | Form 7004 | Sept. 15, 2025 |
| C corporation (C corps) | April 15, 2025 | Form 7004 | Oct. 15, 2025 (calendar-year filers) |
Tax tip: If your original due date was March 15 or April 15 and you requested a filing extension, your extended tax filing deadline will be either Sept. 15 or Oct. 15 — unless that date lands on a weekend or holiday, in which case the next business day applies.
What forms do I need to file after a small business tax extension?
The IRS forms you’ll need depend on your business entity type:
- Sole proprietorships – Schedule C attached to your individual income tax return (Form 1040).
- Partnerships – Form 1065, plus Schedule K-1 for each partner to report their share of business income.
- S corps – Form 1120-S, plus Schedule K-1 for each shareholder.
- C corps – Form 1120 for corporate tax returns.
- LLCs – Varies depending on whether the limited liability company is taxed as a sole proprietorship, partnership, or corporation.
Need a hand gathering what you need? Check out our helpful tax preparation checklists. We have a checklist for each business type so you can stay organized and ensure you’re ready to file.
Tax tip: Remember, filing Form 7004 or Form 4868 only extends your time to file, not to pay. If you still have an unpaid tax balance, you could owe penalties and interest.
Tips for filing your extended business return on time
- E-file for faster tax refund processing and quicker confirmation that your electronic filing was received.
- Double-check your estimated tax payments to ensure they’re applied correctly.
- Don’t forget employment tax and quarterly tax requirements (if applicable).
- If your deadline falls on a weekend or holiday, remember the next business day rule.
- Make sure all taxpayers listed on the return sign before submitting.
FAQs
The bottom line
Your extension deadline is your final chance to submit your federal tax return without extra penalties. Whether you’re filing as a sole proprietorship, partnership, S corporation, or C corporation, knowing your business tax deadlines and required tax forms will help you wrap up this tax season without any added stress.
TaxAct can help you finish your tax filing quickly and accurately — even if you filed your extension request elsewhere. Ready to check “file my business tax return” off your to-do list before the last day? Let TaxAct Business help you file your return.
This article is for informational purposes only and not legal or financial advice.
All TaxAct offers, products and services are subject to applicable terms and conditions.
