March 2026 Business Tax Calendar: Deadlines You Can't Miss

For business owners in the Dallas-Fort Worth area and across the country, March signifies a shift from the initial year-end cleanup to the heavy lifting of tax season. While January and February are often focused on gathering data, March is when significant returns must be filed or extended. At MJ Ahmed CPA PLLC, we know that missing these dates can lead to unnecessary penalties, so we have outlined the critical milestones for this month below.

March 2: The Paper Filing & Industry-Specific Deadline

Because March 1 falls on a Sunday this year, several deadlines roll over to Monday, March 2. This date primarily affects businesses filing information returns on paper and specific industries like agriculture.

Information Returns (Paper Filings)

If your business still files paper forms, this is your deadline for sending government copies of Form 1099 (excluding 1099-NECs which were due earlier) and Form 1096. This also applies to payers of gambling winnings filing Form 1096 and W-2G. However, we strongly encourage shifting to electronic filing, which generally grants you more time (until March 31) and reduces processing errors.

Accountant reviewing financial data for March deadlines

ACA Reporting for Large Employers

Applicable Large Employers (ALEs) filing paper Forms 1094-C and 1095-C must submit them to the IRS by this date. Other providers of minimum essential coverage filing paper Forms 1094-B and 1095-B face the same deadline. Additionally, this is the due date to provide the recipient copies (Form 1095-B or 1095-C) to employees and responsible individuals.

Farmers and Fishermen

For our clients in the agricultural sector, March 2 is the due date to file your 2025 income tax return (Form 1040) and pay any tax due, unless you paid your estimated tax by January 15.

March 16: The Major Business Deadline (Partnerships & S Corps)

This is arguably the most critical date in March for many of our small to mid-sized business clients. Since the standard March 15 deadline falls on a Sunday, you have until March 16 to file or extend.

S Corporations (Form 1120-S) & Partnerships (Form 1065)

Calendar year S Corporations and Partnerships must file their 2025 income tax returns by today. Crucially, this is also the deadline to issue Schedule K-1s to your shareholders and partners. These individuals cannot file their personal returns until they receive their K-1s, so delays here cause a ripple effect.

If your books aren't quite ready, we can file Form 7004 to request an automatic 6-month extension. Remember, an extension to file is not an extension to pay. If you expect to owe taxes (which is more common for S Corps on the entity level in certain jurisdictions), payments should be estimated and made now to avoid interest.

Business owner analyzing tax forms

S Corp Elections (Form 2553)

Strategic tax planning often involves choosing how your entity is taxed. If you intend for your LLC or corporation to be taxed as an S Corp for the calendar year 2026, you must file Form 2553 by March 16. Missing this window usually means the election won't take effect until 2027 unless you qualify for specific relief provisions.

March 31: Electronic Filing Deadline

The IRS continues to push for digital efficiency. If you file electronically, you get the benefit of a later deadline for several information returns.

  • Forms 1099, 1098, and W-2G: Electronic filings with the IRS are due today.
  • ACA Forms (ALE): Electronic filings of Forms 1094-C, 1095-C, 1094-B, and 1095-B are due.
  • Tip Reporting: Large food and beverage establishments filing Form 8027 electronically must do so by today.

Disaster Relief and Extensions

With 25 years of experience helping clients across the U.S., we know that weather events can disrupt business operations. If your business is located in a federally designated disaster area, your deadlines may differ. We monitor these announcements closely, but you can also verify the status of your location below:

Abstract colorful waves representing flow of business finance

Managing these dates alongside daily operations can be stressful. Whether you need to file an extension for your partnership or need clarity on S Corp elections, MJ Ahmed CPA PLLC is here to help ensure your compliance is handled with precision.

Need help finalizing your return or filing an extension? Contact us today to schedule a consultation.

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