Quick answer: GST20 is the election that changes how often you file GST/HST. Filing more often is always open to you. Filing less often is not — the CRA keeps you on your assigned period until you elect out of it.
What the form is
Your reporting period is assigned, not chosen. The CRA sets it from your annual taxable supplies in the previous fiscal year: $1,500,000 or less is annual, more than that up to $6,000,000 is quarterly, and above $6,000,000 is monthly. Charities are assigned annual.
Form GST20 is how you elect out of the period you were assigned. If you were assigned annual or quarterly, you can elect a more frequent period at any time.
Moving the other way is harder. If you were assigned monthly or quarterly, you can only elect a less frequent period once your taxable supplies have sat below the threshold of your assigned period for 12 months.
Who files it
Any GST/HST registrant who wants to file on a different cycle from the one the CRA assigned.
Most often it is a business regularly in a refund position electing to file monthly or quarterly, so the refunds arrive sooner instead of being held until year-end.
The form at a glance
| Item | Detail |
|---|---|
| $1,500,000 or less | Assigned annual |
| Over $1,500,000 up to $6,000,000 | Assigned quarterly |
| Over $6,000,000 | Assigned monthly |
| Electing more often | Available to annual and quarterly filers at any time |
| Electing less often | Only after 12 months below your assigned threshold |
What to have ready before you file
Most of the delay on these is not the form, it is assembling what the form asks for. Have the current reporting period, the period being elected, the effective date, the annual taxable supplies figure that determines eligibility, and confirmation the twelve-month condition is met where a less frequent period is wanted to hand before starting.
Gathering it first also surfaces the problems early, a missing account number, a balance nobody has actually calculated, a date that does not line up — while there is still time to fix them rather than after a filing has been rejected.
What catches people out
The period does not adjust itself downward. The CRA is explicit: if your annual taxable supplies fall below the threshold of your assigned period, your reporting period will not change automatically. Without an election you keep the period you had, so a shrinking business can spend years filing monthly for no reason.
Electing to file more frequently is worth real money if you are usually claiming refunds, because input tax credits come back on each return rather than waiting for one annual filing.
The revenue figure is not simply your sales. Annual taxable supplies include zero-rated supplies and the taxable supplies of your associates, and exclude supplies made outside Canada, zero-rated exports, exempt supplies, sales of capital real property and goodwill.
A late, amended or revoked election carries a penalty of the lesser of $8,000 and $100 for each complete month from the election’s original due date to the date the request reaches the CRA in a form it finds satisfactory. The CRA will generally not process the election until it is paid.
How it is filed
Send it to the CRA, or file the election through My Business Account. The change takes effect from the fiscal period elected, so filing it partway through a period does not retroactively change the deadlines already passed.
Whichever route applies, keep the signed copy and the working papers behind it together. An election is only as defensible as the file that shows how the figures in it were arrived at, and that file is what a review asks for rather than the form itself.
Common questions about GST20
How do I change how often I file GST?+
Can I file less often now that my revenue has dropped?+
Why would I choose to file more often?+
What counts toward the revenue threshold?+
Where this comes from
- CRA — Make changes to your GST/HST account, reporting period
- CRA — Penalty for accepting a late, amended or revoked election
General information current as of August 2026, not advice for your situation. Elections are unforgiving about dates — confirm yours before you file. Please speak with a CPA about your circumstances.
Related reading
- Prescribed interest rates on arrears
- GST/HST filing deadlines by frequency
- Instalments for annual GST filers
- All CRA forms we cover
Other CRA forms
Who does this work
Changing the reporting period changes every deadline that follows it. The filing has to keep up with the election, which is where the penalty usually comes from.
If that is where you are, the service page for file GST/HST on the period you elected sets out what the engagement covers and how it is quoted.
Elections are date-driven and unforgiving. Email us before the deadline rather than after — we quote the work in writing first.
Email us about GST20Have a question about this?
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Changing a reporting period changes how often the books have to be closed, which is a question about the bookkeeping and filing that follow the election.
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