Canada Bookkeeping Guide for Small Businesses and CPA Firms
Running books for a Canadian business means tracking 4 things CRA cares about most: GST/HST, payroll remittances, T4 slips and the records behind every claim. This guide pulls Senvora Group’s Canada articles into one place, with the key dates and rules for 2026 and 2027.
In short: register for GST/HST once taxable sales pass $30,000 over four calendar quarters, remit payroll on time (most employers by the 15th of the next month), file T4 slips by March 1, 2027, and keep proof for every input tax credit you claim.
Key Canada dates to plan around
| What | Date |
|---|---|
| GST/HST return and payment, quarter ending Sep 30, 2026 | Mon, Nov 2, 2026 |
| Payroll remittances, regular remitters | 15th of the following month |
| T4 and T4A slips and summary for 2026 | Mon, Mar 1, 2027 |
Dates come from canada.ca. Always confirm your own dates with your accountant.
Do I need to register for GST/HST?
Most businesses must register once taxable sales pass $30,000 over four consecutive calendar quarters, or in a single quarter. You then have 29 days to register. Read the full rule in GST/HST registration: the $30,000 rule explained.
When are GST/HST returns due?
Quarterly filers with a quarter ending September 30, 2026 must file and pay by Monday, November 2, 2026. Late filing costs 1% of the amount owing plus 25% of that 1% for each full month late, up to 12 months. See Canada GST/HST filing and payment deadlines.
What GST/HST can I claim back?
Input tax credits let you recover GST/HST paid on business costs. Most registrants have 4 years to claim, meals and entertainment are usually limited to 50%, and invoices of $100 or more need extra detail. Full list in GST/HST input tax credits: what you can claim.
When do I remit payroll deductions?
Regular remitters pay CPP, EI and income tax by the 15th of the month after payday. Late remittances over $500 face penalties of 3%, 5%, 7% or 10% depending on how late they are. See Canada payroll remittance deadlines, dates and penalties.
When are T4 and T4A slips due?
Slips and the summary for 2026 are due Monday, March 1, 2027. Get employee details and payroll totals clean before January. Read Canada T4 and T4A filing deadline.
How Senvora helps Canadian businesses and CPA firms
- Business owners: monthly bookkeeping in QuickBooks Online, GST/HST tracking, payroll support and backlog cleanup.
- CPA firms: white label bookkeeping that comes to your team for review before anything reaches the client.
Frequently asked questions
What is the GST/HST small supplier threshold?
$30,000 in taxable sales over four consecutive calendar quarters, or in a single quarter, for most businesses.
When is the Q3 2026 GST/HST return due?
Monday, November 2, 2026, for quarterly filers whose quarter ends September 30.
How long do I have to claim an input tax credit?
Most registrants have 4 years. Some large businesses and financial institutions have 2 years.
When are 2026 T4 slips due?
Monday, March 1, 2027.
Sources
Last updated October 30, 2026 by Senvora Group.