October 2026 Tax Deadlines for Businesses and Entrepreneurs

At Hays CPA LLC, our goal is to help you maintain complete financial control with fewer surprises. As we move into the fourth quarter, October brings several critical tax deadlines for businesses and self-employed professionals. Whether you operate a growing non-profit here in Staten Island or manage a service-based business worldwide, taking a moment to review these upcoming filing dates, payroll tax deposit requirements, and retirement plan deadlines will ensure your compliance remains firmly on track.

Key October 15 Tax Deadlines

Corporate Tax Returns (Form 1120)

For corporations operating on a calendar year, 2025 income tax returns (Form 1120) are due, along with any outstanding tax, interest, and penalties. Please note that this due date applies only if your business successfully requested an automatic six-month extension by April 15.

Social Security, Medicare, and Withheld Income Tax

If your business operations are subject to the monthly deposit rule, October 15 is the deadline to deposit these specific taxes for payments made during September.

Payroll and Tax Compliance

Nonpayroll Withholding

Similarly, if the monthly deposit rule applies to your business, you must deposit the tax for any nonpayroll payments made in September by the October 15 deadline.

Establishing and Contributing to Retirement Accounts

Establishing a Keogh Account for 2025: For self-employed individuals who received an automatic six-month extension of time to file their 2025 tax return, October 15, 2026, serves as the final day to formally establish a Keogh retirement account if you plan to make a contribution for the 2025 calendar year.

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SEP IRA & Keogh Contributions: This is also the final deadline to contribute to a SEP or Keogh retirement plan for the 2025 calendar year, provided your tax return remains on extension through October 15.

Additional Deadline Guidelines

Weekends and Legal Holidays

Standard tax administration rules apply to these dates. If a designated due date happens to fall on a Saturday, Sunday, or legal holiday, the deadline is automatically extended until the next business day that is not itself a legal holiday.

Corporate Office Building

Disaster Area Extensions

Please note that when a geographical area is designated as a disaster area, tax due dates will be extended. To determine whether a specific area has been designated a disaster area and to review the corresponding filing extension dates, you can consult the following official resources:

Maintain Confidence in Your Tax Compliance

Navigating fall extensions and compliance dates doesn't have to be stressful when you have an expert advisory team acting as an extension of your leadership. By staying ahead of these October deadlines, you can keep your focus on driving growth. If you need clarity on which of these dates applies to your specific situation, contact Hays CPA LLC today to schedule a consultation.

Schedule an Appointment Today!
Please note appointments have a $75 booking fee that will apply as a credit on your invoice, if you choose to proceed with our services.
Book Here!
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