The HST filing deadline for a small business, and why it's not your money.

The short answer: your HST filing deadline depends on the reporting period the CRA gave you. Monthly and quarterly filers file and pay one month after each period ends. Most annual filers file and pay three months after their fiscal year-end. A sole proprietor with a December 31 year-end pays by April 30 and files by June 15.

When is my HST return due?

The CRA assigns your reporting period when you register, based on your revenue from taxable sales. You can choose to file more often than assigned. The periods, from the CRA’s guide for GST/HST registrants:

The due dates, from the CRA’s page on reporting requirements and deadlines:

• Monthly or quarterly: file and pay one month after the period ends. A quarter ending September 30 is due October 31.
• Annual: file and pay three months after your fiscal year-end.
• Annual, sole proprietor, December 31 year-end: pay by April 30. File by June 15.
• Annual, with last year’s net tax of $3,000 or more: you may have to pay quarterly instalments, each due one month after a fiscal quarter ends.

Two rules catch people. A return is due for every period, even a quiet one with nothing to report. And almost every registrant now has to file electronically.

Do I even have to charge HST?

Not until you stop being a small supplier. That happens when your taxable sales pass $30,000 over four consecutive calendar quarters, or in a single quarter. Pass it in a single quarter and you charge HST on the very sale that took you over. Either way, you must register within 29 days. The rate depends on the province: the HST rate is 15% in Prince Edward Island, New Brunswick, and Newfoundland and Labrador, and 14% in Nova Scotia since April 1, 2025.

Why isn't the HST I collect my money?

Because the law says so, in plain words. Under section 222 of the Excise Tax Act, anyone who collects GST/HST is deemed to hold it in trust for the Crown, “despite any security interest in the amount.” The CRA describes businesses as collecting it as agents of the government.

If your business is incorporated, there is a second reason to care. The CRA can assess the directors personally for GST/HST the company did not remit, plus the interest and penalties on it.

What does filing late cost?

If you owe money and file late, the late-filing penalty is 1% of the amount owing, plus 0.25% of the amount owing for each full month late, up to 12 months. On $10,000 owing, three months late, that is $100 plus $75. Interest runs on top, from the due date, at a rate the CRA can change each quarter. Filing on paper when you were required to file electronically costs $100 the first time and $250 each time after.

Where do owners get caught?

From what I saw on the lending side, it was rarely the form. It was the money.

• The float. HST sits in the operating account with everything else. A good quarter feels like cash. The bill arrives a month later, after the cash is spent.
• The annual lump. An annual filer can get to month twelve without having paid anything. Then a whole year of HST is due at once.
• The skipped quiet quarter. No sales does not mean no return.

The fix is dull and it works. Move the HST portion of every deposit into a separate account the day it lands. Pay the CRA from that account and nothing else. If you want a weekly check on it, it belongs on your Friday-morning cash list. The same logic applies to payroll deductions, which are also held in trust.

From the desk

When I read small-business files on the lending side, a CRA balance for HST was one of the first lines I looked for. It told me the business had been using money it was holding for someone else to cover a gap. Clearing it, and showing it stays clear, changes how the whole file reads.

How do I stop worrying about the date?

Hand it to someone who tracks it. HST is filed in every HarperCo monthly scope. The lightest is Books Compliance at $395 a month: books kept current, HST filed, and a clean year-end file on a quarterly close. If you are already behind, a Books Rescue catch-up is $295 for each month behind. The minimum is $885.

Key facts

• HST rates: 15% in Prince Edward Island, New Brunswick, and Newfoundland and Labrador; 14% in Nova Scotia since April 1, 2025 (CRA, GST/HST rates, checked September 28, 2026).
• Small supplier threshold: $30,000 in a single calendar quarter or over four consecutive quarters. Register within 29 days (CRA, when to register).
• Assigned periods: annual at $1.5 million or less, quarterly up to $6 million, monthly above (CRA, RC4022).
• Due dates: one month after a monthly or quarterly period. Three months after year-end for annual filers. April 30 to pay and June 15 to file for a sole proprietor with a December 31 year-end (CRA, deadlines).
• Instalments: possible for annual filers whose prior-year net tax was $3,000 or more (CRA, instalments).
• Late filing: 1% of the amount owing, plus 0.25% of the amount owing for each full month late, up to 12 months (CRA, filing penalties).
• Held in trust for the Crown (Excise Tax Act, s. 222).

Notes like this are general information, not advice on your specific situation — that’s what the kitchen table is for. — Dominic