Key Tax Deadlines for Small Business Owners in 2026

Key Tax Deadlines for Small Business Owners in 2026

Taxes
December 01, 2025•3 min read

Published Date: December 01, 2025

Published By: Jac Cantos, Upcloud Accounting

Knowing the critical tax deadlines is essential for every small business owner. Upcloud Accounting provides a clear guide to the key dates you should mark on your calendar for the 2026 tax season.

Important 2026 Tax Deadlines for Small Businesses

Here's a breakdown of the key dates to watch for, depending on your business structure:

Jan. 31, 2026

  • Deadline for any employees or independent contractors you hired last year (in 2024) to receive their W-2, 1099-NEC for nonemployees, or 1099-MISC tax forms.

March 16, 2026 (due to March 15 falling on a weekend)

  • Deadline to file business income tax returns for partnerships, S corporations, or multi-member LLCs that are taxed as partnerships.

    • Note that this is the deadline for calendar year filers. While most taxpayers fall under this category, there are special exceptions for fiscal-year taxpayers. If your tax year doesn’t start on Jan. 1, you will instead follow the IRS fiscal year due date.

  • Deadline to file Form 2553 to switch your business entity to an S corporation (S corp) for tax year 2026. If you miss this deadline, your business will not be treated as an S corp until calendar year 2027.

April 15, 2026

  • Deadline for C corporations and LLCs taxed as corporations to file their corporate tax returns.

  • Deadline for sole proprietorships (Schedule C), single-member LLCs, and individuals to file their individual income tax returns.

  • Last day for you to make 2025 contributions to traditional and Roth IRAS. Traditional IRA contributions may help lower your taxable income if you meet IRS requirements.

Sept. 15, 2026

  • Deadline to file your partnership or S corporation return if you requested a tax extension.

Oct. 15, 2026

  • Deadline to file your sole proprietorship, multi-member LLC, or corporate return if you requested an extension.

2026 Quarterly Estimated Tax Payment Deadlines

If you owe self-employment tax or receive income requiring estimated tax payments, here are the due dates. Always confirm with the IRS, as these can shift.

  • April 15, 2026 - 2026 First Quarter

  • June 15, 2026 - 2026 Second Quarter

  • September 15, 2026 - 2026 Third Quarter

  • January 15, 2027 - 2026 Fourth Quarter

How to File a Tax Extension as a Small Business Owner

Need more time to file? You can request a tax extension before your regular filing deadline. An extension gives you six extra months to file your return.

  • Sole Proprietors: Typically use IRS Form 4868.

  • Partnerships, LLCs, S Corps, and C Corps: Typically use IRS Form 7004.

Important: A tax extension only extends your filing deadline, not your payment due date. You still need to pay any estimated taxes or additional tax liability on time to avoid penalties.

Staying on top of tax deadlines is crucial for small business success. Upcloud Accounting provides expert guidance to help you navigate the complexities of tax compliance and avoid costly penalties.

Upcloud Accounting: Virtual Outsourced Accounting and Bookkeeping Services in the Philippines

Upcloud Accounting provides reliable, tech-enabled virtual accounting and bookkeeping services designed for startups, freelancers, and growing small businesses across the United States. Our team of experienced accountants and bookkeepers delivers streamlined financial management so you can focus on scaling your business, without worrying about the back-office workload.

We specialize in increasing efficiency, automation, and transparency across your financial operations using modern cloud accounting tools. Whether you're a solo entrepreneur or an expanding company, our flexible and affordable bookkeeping plans ensure you get expert support at every stage of growth. For inquiries, contact our team at [email protected] or visit www.upcloudaccounting.com to learn more.

Disclaimer: This content is for general informational purposes only and should not be considered professional financial or legal advice. For guidance tailored to your specific business needs, please consult with a licensed accountant or tax advisor. For questions, comments, or feedback, feel free to email us at[email protected].

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