Learning Center
We keep you up to date on the latest tax changes and news in the industry.

October 2025 Critical Tax Deadlines for Businesses

As the brisk autumn air takes hold, October emerges with pivotal tax deadlines crucial for the smooth operation of your business. Key due dates for corporate tax filings, payroll, and retirement contributions demand attention to ensure compliance and avoid costly penalties.

October 15 - Corporate Tax Filings

Businesses operating on a calendar year schedule must file their 2024 income tax return using Form 1120. It's essential to remit any taxes, interest, and penalties owed. This deadline applies only if an automatic 6-month extension was secured by April 15.

Image 1

October 15 - Employer Tax Obligations

Employers who adhere to monthly deposit rules must submit their payments for Social Security, Medicare, and withheld income taxes for September 2025 by this date. This requirement also applies to nonpayroll withholding if such rules are in play.

October 15 - Nonpayroll Withholding
Ensure that taxes for payments made in September are deposited in compliance with the monthly rule.

October 15 - Keogh Account Deadline

For self-employed individuals with an automatic tax filing extension, this is the last opportunity to establish a Keogh retirement account for the 2024 tax year.

Image 3

October 15 - SEP IRA and Keogh Plan Contributions
Make final contributions to SEP or Keogh plans for the 2024 calendar year, given an extended tax filing date of October 15.

October 31 - Quarterly Payroll Tax Reporting

Form 941 for the third quarter of 2025 must be filed, along with any undeposited taxes following accuracy of deposit rules. A full tax payment is permissible with a timely filed return if liabilities are under $2,500. If tax deposits were made accurately and punctually for the quarter, you have until November 10 to file.

October 31 - Tax for Small Employers

For certain small employers, any tax liabilities of $2,500 or more for 2025, but less than $2,500 for the third quarter, must be deposited.

October 31 - Federal Unemployment Tax
Where tax obligations surpass $500, remittances through September are due.

Image 2

Weekends & Holidays:

If any deadline falls during a weekend or public holiday, it shifts to the following business day that is not a legal holiday.

Disaster Area Extensions:

When an area is declared a disaster zone, tax deadlines may be extended. For more details on specific regions and extension timelines, visit:

FEMA: https://www.fema.gov/disaster/declarations
IRS: https://www.irs.gov/newsroom/tax-relief-in-disaster-situations

Share this article...

Want tax & bookkeeping tips and insights?

Sign up for our newsletter.

I confirm this is a service inquiry and not an advertising message or solicitation. By clicking “Submit”, I acknowledge and agree to the creation of an account and to the and .
Shelton Financial Management LLC We love to chat!
Please feel free to use the buttons below to use our Ai powered chat assistant or contact us.
Please fill out the form and our team will get back to you shortly The form was sent successfully