GST/HST filing checklist: twelve steps before you hit submit

The CRA assigns it from your annual taxable supplies: $1,500,000 or less files annually, over $1.5M to $6M files quarterly, over $6M files monthly. Your CRA My Business Account expected-returns list is the final word when it disagrees with your memory.

October 31, 2026 is a Saturday, so the CRA's weekend rule moves both filing and payment to the next business day: Monday, November 2, 2026. That covers quarterly filers on July 1–September 30 and monthly filers on September. Bank-initiated payments need their own transit time — start the payment a few business days before November 2, not on the day.

If your GST/HST account is administered by Revenu Québec, you do not file with the CRA at all — your returns go through Revenu Québec (clicSÉQUR). NETFILE's eligibility list explicitly excludes Quebec-administered accounts.

Your business number, the 4-digit access code (printed on the return package the CRA mailed you, or shown in your CRA account since October 2025 — lost it? use "Get a GST/HST access code" online or call 1-800-959-5525), and the reporting period's from/to dates. Treat the access code like a password.

The CRA's printer-friendly working copy is a calculation aid — do the line-by-line math on paper first (total sales on line 101, tax collected on line 103, adjustments on line 104), then key the numbers into NETFILE. Do not mail it back. NETFILE sessions expire after 35 minutes of inactivity and nothing is saved until you certify.

The CRA sets documentary requirements by purchase size: under $100 needs the supplier name, date, and total; $100 or more adds the GST/HST paid and the supplier's registration number; $500 or more adds your name, a description, and payment terms. The single biggest ITC error is a missing supplier GST/HST number on invoices of $100 or more — the CRA can deny the credit for it. Keep records for six years.

Meals and entertainment get only 50% of the GST/HST paid; passenger-vehicle ITCs are capped at the tax on the prescribed cost ceiling. Most registrants have four years from the period the credit could first be claimed (two years for listed financial institutions and businesses over $6M) — claim forgotten ITCs on a later return inside the window; outside it, they are gone.

Free, no CRA account needed: enter your business number, access code, and period dates → enter amounts → review → check the certification box → submit. Keep the 6-digit confirmation number — it means the return is accepted for processing. File every period even when you owe nothing (use the nil-return checkbox).

You cannot use NETFILE when you have no access code, you are filing an election with the return, your account is Quebec-administered, or your rebate is outside the short approved list. File through CRA My Business Account or on paper instead.

An on-time return with an unpaid balance skips the late-filing penalty entirely — only interest runs. The deadline that bites is the filing deadline, never the payment one. Paying without filing leaves an overdue return; filing without paying is legal and penalty-free.

Filing and paying are two acts. Monthly and quarterly filers pay one month after the period ends; annual filers that are corporations pay three months after fiscal year-end; individuals with a December 31 year-end file by June 15 but pay by April 30 — interest starts May 1 on any unpaid balance.

The penalty is 1% of the amount owing plus 0.25% for each full month late, up to 12 months — one month late costs 1.25%, six months costs 2.5%. A $0 balance or refund position carries no late-filing penalty. Never re-file a period to fix an error — adjust through My Business Account ("Adjust a return") or by mailing a signed letter to your tax centre.