A GST/HST return is the return every GST/HST registrant files with the Canada Revenue Agency to report the GST/HST collected from customers, claim input tax credits on business purchases, and settle the difference. You must file one for every reporting period — even when you had no sales. This guide walks through who files, when it’s due, what each line of the return means, how to file online with GST/HST NETFILE, and what late filing actually costs.
Who Has to File a GST/HST Return?
If your business is registered for GST/HST, you file a return. Full stop. Registration is required once your taxable supplies exceed $30,000 in a calendar quarter or over four consecutive quarters (the small supplier threshold), and many businesses register voluntarily below that to claim input tax credits.
The obligation that surprises new registrants: you must file a return for every reporting period, even if you made zero sales and collected zero tax. That’s called a nil return, and skipping it is one of the most common compliance mistakes small businesses make.
How Often Do You File? (Reporting Periods)
The CRA assigns your reporting period based on your annual taxable supplies:
| Annual taxable supplies | Reporting period | Returns per year |
|---|---|---|
| $1,500,000 or less | Annual | 1 |
| More than $1,500,000 up to $6,000,000 | Quarterly | 4 |
| More than $6,000,000 | Monthly | 12 |
Most small businesses file annually. You can elect to file more frequently than required (Form GST20) — for example, switching from annual to monthly gets input tax credit refunds back to you faster if you consistently pay more GST/HST on purchases than you collect. You cannot elect to file less frequently than your assigned period.
GST/HST Return Deadlines
| Reporting period | Return due | Payment due |
|---|---|---|
| Monthly | 1 month after period end | 1 month after period end |
| Quarterly | 1 month after period end | 1 month after period end |
| Annual (corporations, partnerships, trusts) | 3 months after fiscal year-end | 3 months after fiscal year-end |
| Annual (self-employed individuals, Dec 31 year-end) | June 15 | April 30 |
Two things to note. First, the self-employed rule mirrors income tax: you get extra time to file (June 15) but not extra time to pay — interest starts running on any unpaid balance after April 30. Second, if a due date falls on a weekend or a public holiday the CRA recognizes, your return or payment is on time if the CRA receives it on the next business day.
What You Need Before You File
Gather these before you sit down with the return:
- Your Business Number and GST/HST program account number (the 15-digit number ending in RT0001).
- Your reporting period start and end dates — confirm them in CRA My Business Account, because they follow your fiscal year, not necessarily the calendar.
- Total sales and other revenue for the period, before GST/HST — including zero-rated and exempt sales.
- Total GST/HST you collected or that became collectible.
- Your input tax credits: the GST/HST you paid on business expenses, backed by receipts and invoices.
- Any instalments you already paid toward the period.
- For GST/HST NETFILE: your 4-digit access code.
Good bookkeeping is what makes this list painless. If your sales, tax collected, and tax paid are already tracked by tax code in your accounting software, the return is mostly transcription.
How to File Your GST/HST Return Online
Most registrants must now file electronically — paper returns are no longer accepted for most businesses for reporting periods ending in 2024 and later (charities and selected listed financial institutions are the main exceptions). Your options:
- CRA My Business Account — file directly and see your balance, notices, and refund status in one place.
- GST/HST NETFILE — the CRA’s web form. Enter your Business Number and 4-digit access code, fill in the lines, submit, and save the confirmation number as your proof of filing.
- GST/HST TELEFILE — file by phone using a touch-tone line.
- Paper Form GST34 — only if you’re in one of the exempt categories.
Payments of $10,000 or more must also be made electronically — for example, through online banking (add “CRA – GST/HST” as a payee and use your 15-digit account number) or My Business Account.
Understanding the Return, Line by Line
The GST/HST return (Form GST34) looks intimidating, but it asks for a handful of numbers:
- Line 101 — Sales and other revenue: total sales for the period before GST/HST, including zero-rated and exempt supplies.
- Line 103 — GST/HST collected or collectible: the tax you charged customers.
- Line 104 — Adjustments (add): amounts that increase your tax, such as GST/HST on goods taken for personal use.
- Line 105 — Total GST/HST and adjustments: line 103 plus line 104.
- Line 106 — Input tax credits (ITCs): the GST/HST you paid on business purchases and expenses.
- Line 107 — Adjustments (deduct): amounts that reduce your ITCs.
- Line 108 — Total ITCs and adjustments: line 106 plus line 107.
- Line 109 — Net tax: line 105 minus line 108. Positive means you owe; negative means a refund.
- Line 110 — Instalments and other payments: amounts you already paid toward this period.
- Line 111 — Rebates: eligible rebates claimed on the return (for example, certain public service body rebates).
- Line 112 — Total other credits: instalments plus rebates (110 + 111).
- Line 113A/B/C — Balance: net tax minus other credits. A positive balance means an amount owing; a negative balance means a refund.
- Line 114 — Refund claimed: enter the refund amount here if line 113 shows a negative balance.
- Line 115 — Payment enclosed: the amount you’re remitting with the return.
Worked example — amount owing (Ontario, 13% HST): a consultant has $40,000 in sales for the quarter (line 101), collected $5,200 in HST (line 103), and paid $1,300 in HST on business expenses (line 106). Net tax on line 109 = $5,200 − $1,300 = $3,900 owing (line 115).
Worked example — refund: a startup exporter has $60,000 in zero-rated export sales (line 101 — still reported, even though no tax was collected), collected $0 HST (line 103), and paid $2,600 in HST on equipment and supplies (line 106). Net tax on line 109 = $0 − $2,600 = −$2,600, claimed as a refund on line 114. This is exactly why exporters and capital-intensive startups register voluntarily: every dollar of ITC becomes cash back.
What Happens After You File?
Save the confirmation number GST/HST NETFILE gives you — it’s your proof of filing. The CRA then processes the return: electronic returns move faster than paper, and straightforward returns with no review flags are typically the quickest. If line 113 shows a refund, sign up for direct deposit through CRA My Business Account so the money lands in your bank account instead of waiting on a cheque in the mail.
Sometimes the CRA selects a return for review before issuing a refund. That doesn’t mean you’ve done anything wrong — but it does mean having your receipts, invoices, and ITC supporting documents organized and accessible, which circles back to the six-year record-keeping rule. If the CRA adjusts your return, you’ll receive a notice of assessment explaining the change, and you have the right to object if you disagree.
What Happens If You File Late?
The GST/HST late-filing penalty is formula-driven: 1% of the balance owing, plus 0.25% of the balance for each complete month the return is late, up to 12 months. On top of that, interest accrues at the CRA’s prescribed rate, compounded daily, from the payment due date.
Example: a $20,000 balance filed 6 months late attracts a $200 base penalty plus $300 in monthly penalties ($50 × 6) — $500 before interest. File a nil return late and there’s no penalty since nothing is owing, but the return is still legally required, and ignoring a formal CRA demand to file triggers a separate penalty.
Do You Owe Instalments?
If you’re an annual filer and your net tax for the previous year was $3,000 or more, you generally have to pay quarterly instalments during the year even though you only file one return. Missing instalments means interest charges, so this is worth confirming in My Business Account rather than discovering at year-end.
The Quick Method: A Simpler Way for Small Businesses
The CRA’s Quick Method lets eligible small businesses skip detailed ITC tracking. Instead of reporting tax collected minus ITCs, you remit a fixed percentage of your GST/HST-included sales — for example, a service business in Ontario remits 8.8% instead of dealing with the full 13% HST accounting. You can still claim ITCs on large capital purchases.
Eligibility: worldwide taxable supplies of $400,000 or less, in business continuously for the 365 days before the reporting period (new businesses can elect in their first year if they reasonably expect to stay under the threshold), elected on Form GST74. One catch worth knowing if you’re in this industry: businesses providing accounting, bookkeeping, tax consulting, or tax preparation services are excluded from the Quick Method no matter how small they are — but it’s a legitimate planning option for many of your future clients.
Common GST/HST Filing Mistakes to Avoid
- Skipping nil returns. No sales doesn’t mean no return.
- Using the wrong rate. HST is 15% in the Atlantic provinces, 13% in Ontario, 5% GST-only in Alberta and the territories — and Nova Scotia’s HST dropped to 14% in April 2025. Charge based on the customer’s province, not yours.
- Overclaiming ITCs. You can’t claim ITCs on the personal-use portion of expenses, and ITCs generally must be claimed within four years.
- Mixing up filing and payment dates. Self-employed annual filers: payment April 30, return June 15.
- Poor records. Keep all GST/HST records for at least six years from the end of the related tax year — the CRA expects them on audit.
Learn It Properly, Not Just Once a Year
Filing a GST/HST return is a mechanical skill — but doing it confidently, spotting when the Quick Method saves a client money, and handling CRA correspondence is what separates a data-entry clerk from a trusted tax professional. If you want hands-on training in Canadian GST/HST (plus personal and corporate tax) taught by working professionals, look at Get Trained Get Hired’s GST/HST course in Mississauga.
Related reading: our guides to T1 vs T2 tax returns and tax preparer certification in Canada.
Frequently Asked Questions
Do I have to file a GST/HST return if I had no sales?
Yes. Every registrant must file for every reporting period, including periods with no activity — that’s a nil return. The late-filing penalty doesn’t apply when nothing is owing, but the filing obligation stands.
Can I still file my GST/HST return on paper?
For most registrants, no. Electronic filing is mandatory for reporting periods ending in 2024 and later, with limited exceptions (charities and selected listed financial institutions). Paper filing when you’re required to file electronically can lead to penalties.
Where do I find my GST/HST NETFILE access code?
It’s the 4-digit code the CRA sends with your filing notice. If you’ve lost it or it isn’t working, request a new one through CRA My Business Account or by contacting the CRA. Never share it — it’s tied to your account.
How long must I keep my GST/HST records?
At least six years from the end of the tax year they relate to. That includes sales invoices, purchase receipts, contracts, and your ITC supporting documents.
What if I realize I claimed too many input tax credits?
Correct it — usually as an adjustment (line 107) on your next return, or by contacting the CRA for larger errors. Fixing it voluntarily is always cheaper than having an auditor find it.
How do I pay a GST/HST balance owing?
Through online banking (add “CRA – GST/HST” as a payee with your 15-digit account number), CRA My Business Account, or pre-authorized debit. Balances of $10,000 or more must be paid electronically.
