Start with the actual account and reporting period
Confirm the GST/HST account, filing frequency, period end and accounting method before preparing a return. An Ontario business address does not make every sale subject to 13% HST: the type of supply, customer and place-of-supply rules matter. Separate taxable, zero-rated and exempt revenue in the records.
A typical small supplier’s $30,000 registration test concerns worldwide taxable supplies, including relevant associated businesses. Exceeding it in one calendar quarter has different timing consequences from exceeding it across consecutive quarters. Review a registration change separately from the quarter-end arithmetic.
Work through the reserve calculation
Illustrative regular-method quarter: tax collected or collectible is $6,500, eligible input tax credits are $1,700, a supported net adjustment increases tax by $100, and $1,000 in payments has already been made for this period. The remaining planning amount is $3,900: $6,500 − $1,700 + $100 − $1,000.
That example assumes the credits and adjustment are valid. A supplier invoice is not automatically a fully recoverable credit: personal use, exempt activities and other restrictions can change the result. The calculator does not make those determinations.
Before the quarter is closed
- Reconcile sales reports and processor settlements to revenue and the tax control account.
- Include tax collectible on applicable unpaid invoices, rather than using bank receipts alone.
- Check supplier invoices, credit notes and refund records supporting tax credits.
- Separate GST/HST from QST, PST, municipal taxes and customs duty.
- Reconcile payments and instalments to the correct CRA account and period.
- List unresolved tax codes or cross-province transactions for the preparer.
Keep the deadline and evidence together
For a September 30 quarter-end, the ordinary deadline is October 31. In 2026 that date falls on a Saturday, so CRA’s next-business-day rule makes November 2, 2026 the filing and payment date. Allow time for the selected payment method to arrive.
Save the filed return, calculation, payment confirmation and explanation of any adjustment together. This makes the next quarter’s opening balance easier to reconcile and distinguishes an amount owing on the return from other CRA account items.
Put this into practice
Sources and current guidance
A practical next step
Bring the records you have.
We can identify missing information, agree on the scope and organize the next bookkeeping step.
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