September Canadian Business Due Dates & Three Fabulous Business Resources!


Hello Reader!

Welcome to August 31st 2025! In this Newsletter:

  • What’s due at the end of August?
  • My Three Favorite Resources for September!
  • What due dates are coming up in September?

What’s Due End of August?

Note that Aug 31st falls on a Sunday this year, and Labour Day is Monday Sept 1st. When this happens, the CRA Deadline falls to the next business day, in this case, September 2nd for all Aug 31st noted deadlines below.

  • If you are incorporated, and you owed greater than $3k in corporate Income Tax for your previous fiscal year, then you are required to pay installments for next year on the last day of every month. August 31st is the due date for the August Corporate Tax Installment.
  • Though there are no other standard items due at the end of this month, be aware that if your Sales Tax filing is monthly, July's GST/HST filing and remittance is due on August 31st. If your Sales Tax quarterly filing is on a different schedule because of a corporate fiscal year end date that is not standard, the GST/HST for a quarter May to July would be due Aug 31st. Also, if your Corporate Fiscal Year End is February, your Corporate Tax Return is due 6 months after your Fiscal Year end (August 31st). If your Corporate Year End is June, the Income Tax Payable is payable 2 or 3 months after the Fiscal Year End; either due end of August or end of September, depending on your corporation. Check in with your accountant to find out more about your corporate tax due dates specific to your corporation.

My Three Favorite Resources for September!

  1. Pay Strategies for Canadian Business Owners: When to incorporate? After incorporation, what should the shareholder's compensation plan be? Avalon Accounting put together a great article on real life scenarios of Canadian Business owners! Check it out here!
  2. CRA Penalty Calculator: How much would you owe for 2023's tax year if you filed and paid May 5th 2025, had self employment income, and had tax payable of $5k? I plugged in those numbers to this Canadian Personal Tax Penalty Calculator from Copilot Tax, and the total penalties and interest came to $1,278! On only $5k payable!!! Did you expect closing one's eyes to getting one's taxes done to cost so much!? Try playing around with some bigger numbers! Use this information to burn that fire under you, or to warm your marshmallows on as a reward for staying on top of your business bookkeeping. It may feel unrewarding to stay on top of your taxes, but I've seen the other side, and you deserve a pat on the back! Many pay the literal price for not making it a priority! #DontGiveCRAMoreMoneyThanYouHaveTo
  3. Labour Day Legislation Explained: Labour Day in Canada is observed on the first Monday of September and is recognized as a statutory holiday in every province and territory. In this guide from PayTrak, you’ll find a summary of Labour Day requirements for each Canadian jurisdiction.

What Resources have you found that have helped you start, run, or grow your business? Feature it (and a callout to your business!) in our next Resources Newsletter!

What due dates are coming in September?

Now’s the time to prep your September Calendar! #BeThatBusiness that is organized! Here are some September due dates that might affect your business:

  • If you have employees, September 15th is the due date for your payroll source deductions relating to August's payroll if you are a regular remitter.
  • If you have employees, then you likely are registered for provincial Workplace Insurance (WSIB/WCB). WCB in some provinces is due monthly, and on the 15th. In Ontario, WSIB is due quarterly, and the premiums on earnings from July to Sept are due on Oct 31st.
  • If you owed greater than $3k in personal income tax for two years in a row, then you are required to pay quarterly installments for next year. They don't match the business quarterly schedule though. September 15th is the next personal income tax installment due date.
  • If you are incorporated, and you owed greater than $3k in corporate Income Tax for your previous fiscal year, then you are required to pay installments for next year on the last day of every month. September 30th is the due date for the September Corporate Tax Installment.​
  • Though there are no other standard items due at the end of this month, be aware that if your Sales Tax filing is monthly, August's GST/HST filing and remittance is due on September 30th. If your Sales Tax quarterly filing is on a different schedule because of a corporate fiscal year end date that is not standard, the GST/HST for a quarter June to August would be due September 30th. Also, if your Corporate Fiscal Year End is March, your Corporate Tax Return is due 6 months after your Fiscal Year end (September 30th). If your Corporate Year End is July, the Income Tax Payable is payable 2 or 3 months after the Fiscal Year End; either due end of September or end of October, depending on your corporation. Check in with your accountant to find out more about your corporate tax due dates specific to your corporation. Check out CRA's "Quick Reference Guide" for more information.

Be Intentional Today!
Get out there, and Be That Business That Thrives!

Naomi Wilkins
I Love Making Bookkeeping Make Sense

www.naomiwilkins.ca

Let's Get Social!

Disclaimer: This Newsletter is intended to inform readers in general terms. It is not intended to provide any tax or business advice. Please consult your accountant if you have any questions about your unique situation. While I have tried to ensure the accuracy of the information in this newsletter, I accept no liability for errors or omissions.

Be That Business Newsletter

You want to "Be That Business" – the one that's organized, informed, and thriving. But to get there, you need to understand how your business actually works. That's where the "Be That Business Newsletter" comes in. Each month, you'll receive essential Canadian business deadlines for the month ahead, plus practical tips and resources to help you master your records, data processes, and the inner workings of your business. Let's move beyond just ticking boxes and build a business with intention. You cannot manage what you do not monitor, but knowing what and how to monitor efficiently and accurately avoids wasted time, money, and double work. Compliance is the foundation, but understanding how your business actually works and leveraging that information and data for growth? That’s where the magic happens! ✨

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