When are business taxes due for LLCs?

The LLC filing deadline depends on tax classification. Single-member LLCs file by April 15. Multi-member LLCs classified as partnerships file by March 16. LLCs electing S corp status file by March 16. LLCs electing C corp status file by April 15.

What is the deadline for corporate tax returns?

C corporations must file Form 1120 by April 15, 2026, for calendar-year filers. S corporations file by March 16, 2026. The deadline for corporate tax returns extends six months with Form 7004. However, you must pay estimated taxes by the original deadline.

When do LLC have to file taxes?

When does an LLC have to file taxes varies by classification. Partnership-taxed LLCs file March 16. Sole proprietor LLCs file April 15. The tax return due date for LLC entities can be extended but requires timely filing of extension forms.

What happens if I miss a tax deadline?

Late filing penalties start at 5% of unpaid taxes per month, up to 25%. Late payment penalties are 0.5% per month. Interest also accrues on unpaid balances. File as soon as possible to minimize penalties.

Can I file an extension for my business taxes?

Yes. Partnerships and S corps use Form 7004, extending the deadline to September 15. C corps also use Form 7004, extending to October 15. Sole proprietors use Form 4868, extending to October 15. Remember that extensions don't postpone payment deadlines.

How do I pay quarterly estimated taxes?

Use Form 1040-ES for individuals and sole proprietors. Corporations use Form 1120-W calculations. Pay online through EFTPS, IRS Direct Pay, or credit card. You can also mail a check with payment vouchers.

Are state tax deadlines the same as federal deadlines?

Not always. While some states align with federal deadlines, many have different due dates. Check your state's tax agency website for specific requirements. Some states also require additional filings like franchise tax returns or gross receipts tax reports.

What forms do I need for employee taxes?

Employers file Form 941 quarterly for federal payroll taxes. You must also file Form 940 annually for federal unemployment tax. Provide W-2 forms to employees by January 31. File copies with the Social Security Administration by the same date.

When are taxes due March 15?

The actual date for partnerships and S corporations in 2026 is March 16 (March 15 falls on a Sunday). This deadline applies to Form 1065 and Form 1120-S. This is earlier than the April 15 deadline to allow partners and shareholders time to file personal returns.

What is the business tax extension deadline?

The business tax extension deadline varies by entity type. S corps and partnerships get until September 15. C corps and sole proprietors extend to October 15. File extension forms (7004 or 4868) by the original deadline to qualify for the extension.

Business Tax Deadlines for 2026: What Corporations & LLCs need to know?

Business Tax Deadlines for 2026: What Corporations and LLCs need to know?

Understanding business tax deadline requirements is critical for staying compliant. Missing important dates can result in penalties, interest charges and financial stress.

This guide covers all the essential corporate tax deadlines, and LLC filing deadline dates for 2026. Whether you run a corporation, S corp, partnership or LLC, you’ll find everything you need to know about the business tax deadlines.

Key takeaways

Mark key tax dates: March 16 (S corps/partnerships) and April 15 (C corps/sole proprietors).
File Form 7004 or Form 4868 on time to extend filing, not payment.
Track quarterly estimated payments: April 15, June 15, September 15 and January 15.
Remember that payroll and information return deadlines (W-2, 1099) fall on January 31, 2026, and the updated Q4 payroll tax deadline is February 2, 2027.
Keep records organised and coordinate with a CPA early for strategic tax planning.
Confirm state-specific filing dates, as they often differ from IRS due dates.
Meeting deadlines builds financial credibility, avoids costly penalties, and preserves business cash flow.

What are different business tax filing deadlines for each entity?

The business tax deadlines varies depending on your company structure. Each entity type has specific due dates and requirements that you must follow.

Partnership & LLC tax deadlines

Partnerships and multi-member LLCs typically file as pass-through entities. They must report income using Form 1065.

Partnership filing deadline: March 16, 2026

This is when partnership tax returns are due. The IRS requires partnerships to submit Form 1065 by this date for the 2025 tax year.

Pass-through entities do not pay tax at the entity level. Instead, they distribute profits and losses to partners or members through Schedule K-1 forms.

Extension available: You can file Form 7004 to get an automatic extension. This moves your filing deadline for corporate tax returns to September 15, 2026.

However, the extension only gives you more time to file. It doesn’t extend the time to pay taxes owed.

Conclusion

Understanding tax deadlines prevents penalties and maintains compliance. Whether you operate a C corporation, S corp, partnership, or LLC, marking these dates on your calendar is essential.

The corporate tax deadlines for 2026 fall on March 16 for partnerships and S corps. C corporations and sole proprietors file by April 15.

Don’t forget quarterly estimated tax payments throughout the year. These deadlines apply to most business structures and help you avoid underpayment penalties.

Working with a qualified CPA or tax professional can save time and money. They help identify deductions, ensure accuracy, and provide strategic guidance.

Start preparing now for a smooth 2026 tax season. Organization and proactive planning make the process less stressful and more efficient.