Tax Deadlines Every Small Business Owner in Texas Should Know in 2026

Taxes don’t wait, and neither does the IRS. If you own a business in Texas, you’re dealing with a mix of federal filing deadlines, quarterly payment schedules, and a state franchise tax that catches people off guard every single year.

Here’s the complete breakdown — organized by entity type, so you can find what actually applies to you.

A Note on Texas and State Income Tax

Good news first: Texas has no state income tax. That’s not just a perk — it’s constitutionally prohibited. But don’t let that lull you into thinking the state leaves you alone. Texas has its own Franchise Tax (sometimes called the margin tax), and most businesses still have to file something with the Comptroller every year, even if they owe nothing.

More on that below.

Federal Deadlines by Entity Type

Sole Proprietors & Single-Member LLCs

These flow through to your personal return (Form 1040, Schedule C).

• April 15, 2026 — 2025 return due. Also the deadline for your Q1 2026 estimated tax payment.
• October 15, 2026 — Extended return due (if you filed Form 4868 by April 15)

Partnerships & Multi-Member LLCs

File Form 1065 and issue K-1s to each partner.

• March 16, 2026 — Return due. (March 15 falls on a Sunday, so it shifts to Monday.)
• September 15, 2026 — Extended return due (file Form 7004 by March 16).

Watch out: The late filing penalty for partnerships is $220 per partner, per month, for up to 12 months — even if no tax is owed. A 3-partner LLC that files two months late owes $1,320 before anything else is even considered.

S Corporations

File Form 1120-S and issue K-1s to each shareholder.

• March 16, 2026 — Return due. Same Sunday shift as partnerships.
• September 15, 2026 — Extended return due (file Form 7004 by March 16).

Late filing penalty: Approximately $245 per shareholder per month in 2026, for up to 12 months. This adds up fast for multi-owner S Corps.

C Corporations

File Form 1120.

• April 15, 2026 — Return and any tax due.
• October 15, 2026 — Extended return due (file Form 7004 by April 15).

Quarterly Estimated Tax Payments

If your business doesn’t withhold taxes automatically (most small businesses don’t), you’re responsible for paying taxes in four installments throughout the year. Missing these doesn’t just create penalties — it creates a cash flow crisis at year-end.

Sole proprietors and self-employed individuals use Form 1040-ES. C Corporations use Form 1120-W to calculate and track estimated payments.

Payroll & Employment Tax Deadlines

If you have employees, you have a whole separate set of deadlines running parallel to everything above.

• February 2, 2026 — W-2s must be in employee hands.
• Quarterly (April, July, October, January) — Form 941 for federal income tax, Social Security, and Medicare withheld from employee paychecks.
• Annually — Form 940 for federal unemployment tax (FUTA).

Payroll tax deposits (monthly or semi-weekly) are separate from the quarterly reporting. Your deposit schedule depends on your lookback period tax liability — if you’re unsure which schedule applies to you, this is worth a conversation with your accountant.

1099 Deadlines

If you paid any contractor or vendor $600 or more in 2025, you likely need to file.

• February 2, 2026 — 1099-NEC and 1099-MISC must be sent to recipients.
• March 2, 2026 — Paper filing deadline with the IRS.
• March 31, 2026 — Electronic filing deadline with the IRS.

The Texas Franchise Tax — Don’t Skip This One

This is the deadline most Texas business owners miss.

May 15, 2026 — Texas Franchise Tax return and payment are due for the 2025 tax year.

Here’s what makes it different from everything else:

• It’s based on revenue, not net income — technically called the “margin tax.” You could have a federal loss and still owe franchise tax.
• If your total revenue is at or below $2.47 million (verify this threshold annually), you file a No Tax Due Report instead of paying tax. But you still have to file. Skipping the report — even when you owe nothing — puts your good standing with the Comptroller at risk.
• Need more time? File Form 05-164 by May 15 for an automatic extension to November 15, 2026. Unlike federal extensions, the Texas franchise tax extension generally aligns with your federal extension if you’ve already filed Form 7004 or 4868.

Common mistake: People assume the franchise tax follows the April 15 rhythm. It doesn’t. May 15 is its own deadline, and it shows up in a completely different season than everything else.

Extensions: What They Actually Do (and Don’t Do)

Extensions give you more time to file. They don’t give you more time to pay.

If you owe taxes and you file an extension, you still need to estimate what you owe and pay it by the original due date. Failure to pay on time means interest and a failure-to-pay penalty starts accruing — even if your return eventually gets filed on time.

This is one of the most common (and expensive) misunderstandings in small business taxes.

Quick Reference Summary

Need Help Staying on Top of This?

Managing deadlines is one thing. Managing them while running a business is another. At Mockingbird Accounting, we work with small business owners in Texas to keep filings accurate, on time, and penalty-free.

If you’d like a second set of eyes on your situation — or just want to know what actually applies to your business — schedule a free consultation.

This article is for informational purposes only and does not constitute tax or legal advice. Tax laws change — always verify current rules with a qualified tax professional.