GST/HST filing deadlines for Ontario businesses in 2026

Last updated: October 18, 2026

Most Ontario businesses registered for GST/HST must file their return and remit payment within one month after each reporting period ends. Annual filers generally get three months after their fiscal year-end, though there is a notable exception: sole proprietors with a December 31 year-end must pay by April 30 but can file as late as June 15. These are the core GST/HST filing deadlines every Ontario registrant needs to know.

Here is the short version by frequency:

• Monthly and quarterly filers: return and payment both due one month after the reporting period ends
• Annual filers (most businesses): return and payment due three months after fiscal year-end
• Annual filers (sole proprietors, December 31 year-end, business income): payment due April 30; filing due June 15

For reporting periods beginning in 2024 and later, electronic filing is mandatory for most registrants. Paper returns are no longer an option unless you qualify for a specific exemption.

Your personalised due dates live in CRA My Business Account. Log in, confirm your reporting period, and set calendar reminders now. If you want someone to manage that for you, T-Ledgers can help.

Key takeaways

Ontario GST/HST registrants must file electronically for all reporting periods beginning in 2024, with returns and payments due one month after each period for monthly and quarterly filers, and three months after fiscal year-end for most annual filers.

Table of Contents

• Who must register and how the CRA assigns your reporting period
• Concrete deadline calendar and worked examples for Ontario businesses in 2026
• When payments are due versus when you file: instalments and timing
• Mandatory electronic filing and how to file your GST/HST return
• Late-filing penalties and interest: what they cost and how to get relief
• How to change your reporting period, register, or deregister
• Common filing mistakes Ontario businesses make and a compliance checklist
• Research-backed workflows to prevent missed deadlines
• Special considerations for businesses affected by unforeseen events
• How T-Ledgers approaches GST/HST deadlines for Ontario clients
• GST/HST filing support for Ontario businesses from T-Ledgers
• Sources
• FAQ

Who must register and how the CRA assigns your reporting period

Any business whose worldwide taxable supplies exceed $30,000 in a single calendar quarter or in four consecutive calendar quarters must register for GST/HST. Once you cross that threshold, you must register within 29 days of the supply that pushed you over it. Voluntary registration is also available for businesses below the threshold, and it is often worth doing if you want to claim input tax credits (ITCs) on your purchases.

Once you are registered, the CRA assigns your reporting period based on your annual taxable supplies. The thresholds come from CRA’s general information for registrants:

The CRA assigns these periods automatically based on the revenue you reported in prior years. If your business grows past a threshold, you are expected to notify the CRA proactively. Waiting for the CRA to catch up can create a gap where you are filing on the wrong schedule.

Pro Tip: Many businesses with significant input tax credits elect to file monthly even when they qualify for quarterly or annual reporting. Filing more frequently accelerates ITC refunds, which improves cash flow. To make that election, contact the CRA directly or use CRA My Business Account. The election generally takes effect at the start of your next fiscal year.

Concrete deadline calendar and worked examples for Ontario businesses in 2026

The deadline for monthly and quarterly filers is one calendar month after the last day of your reporting period. Annual filers follow the three-month rule, with the sole-proprietor exception noted above.

Sample due dates for common reporting periods in 2026

Worked example 1: quarterly filer in Toronto

A Toronto-based marketing agency files quarterly. Its Q1 2026 reporting period runs January 1 to March 31, 2026. One month after March 31 is April 30, 2026. Both the GST62 return and the remittance are due April 30, 2026. If April 30 falls on a weekend or public holiday, the deadline shifts to the next business day.

Worked example 2: annual sole proprietor in Mississauga

A Mississauga-based freelance designer files annually with a December 31 year-end and reports business income. The filing deadline is June 15, 2026. The payment deadline is April 30, 2026. Filing late on June 16 triggers a penalty. Paying late on May 1 triggers interest. These are two separate deadlines, and missing either one has its own cost.

When payments are due versus when you file: instalments and timing

For monthly and quarterly filers, the payment and filing deadlines are the same: one month after the period ends. Annual filers face more complexity. Most pay and file at the same time, three months after fiscal year-end. The sole-proprietor exception splits those dates, as shown above. One rule applies across all categories: you must remit GST/HST for invoices you included in your return even if your customer has not paid you yet.

Instalment obligations

Some annual filers must remit quarterly instalments during the year rather than one lump sum at year-end. You are generally required to remit by instalment if your net tax for the previous year exceeded $3,000. Instalments are due one month after each quarter ends, and the CRA will tell you if you are required to make them. Missing an instalment does not trigger a late-filing penalty, but it does generate interest on the shortfall.

If you cannot pay on time, here is what to do:

• File your return on time regardless. Filing without paying stops the failure-to-file penalty clock. Interest on the unpaid balance continues, but the penalty does not compound further.
• Contact the CRA as soon as possible to discuss your options.
• Consider a payment arrangement if you cannot pay the full amount at once.
• Do not wait for a CRA notice before acting. The interest rate on overdue GST/HST balances is set quarterly and compounds daily.

Processing lead times matter. When paying through a financial institution or a third-party processor, allow two to three business days for the payment to reach the CRA. The CRA considers a payment received on the date the financial institution processes it, not the date you initiate it. For electronic returns, the CRA deems the return filed on the day it confirms acceptance.

Mandatory electronic filing and how to file your GST/HST return

For reporting periods beginning in 2024 and later, most GST/HST registrants must file electronically. Charities and selected listed financial institutions are the primary exceptions. Filing on paper when electronic filing is required carries an administrative penalty: $100 for a first occurrence and $250 for each subsequent return filed on paper.

Accepted filing methods

1. CRA My Business Account — the most direct route. Log in at canada.ca, navigate to your GST/HST account, and file using the online form. You can also view your personalised due dates and account balance here.
2. Represent a Client — if your accountant or bookkeeper files on your behalf, they use this CRA portal. You must authorize them as a representative on your CRA account before they can access or file.
3. Third-party accounting software — software certified for CRA NETFILE (such as QuickBooks, Sage, or Xero) can transmit your return directly to the CRA. Confirm your software version is CRA-certified for the current year.
4. Financial institutions — some banks allow GST/HST remittances through online banking. This method handles payment but may not file the return itself. Confirm with your bank which steps it covers.

How to file through CRA My Business Account

1. Log in to My Business Account at canada.ca.
2. Select your GST/HST account from the account list.
3. Choose “File a return” and select the correct reporting period.
4. Enter your total sales, taxable supplies, and ITCs. If you are unsure how to calculate your ITCs, the T-Ledgers guide on calculating HST returns walks through the method step by step.
5. Review the net tax owing or refund amount.
6. Submit and save your confirmation number.

If you are authorizing a representative, do that first under “Manage authorized representatives” in My Business Account. Your representative cannot file until that authorization is active.

Late-filing penalties and interest: what they cost and how to get relief

The late-filing penalty formula is 1% of the amount owing on the due date, plus 0.25% of that same amount for each complete month the return remains overdue, up to a maximum of 12 months. Interest is charged separately on any overdue balance, compounded daily at the CRA’s prescribed rate.

How the penalty adds up: a worked example

Suppose an Ontario business owes $10,000 in net GST/HST and files three months late.

• Base penalty: 1% of $10,000 = $100
• Monthly addition: 0.25% × $10,000 × 3 months = $75
• Total penalty: $175

That is before interest on the $10,000 balance, which compounds daily from the original due date. Interest accrues daily at the CRA’s prescribed rate, which is adjusted quarterly. The combined cost of filing three months late on a $10,000 balance is approximately $400, and it grows every day the return stays unfiled.

One practical point practitioners consistently make: file the return even when you cannot pay. If there is no amount owing, there is no failure-to-file penalty. If there is an amount owing, filing on time stops the penalty from accruing while you arrange payment.

Taxpayer relief

The CRA’s taxpayer-relief process allows the CRA to cancel or waive penalties and interest in extraordinary circumstances, such as serious illness, natural disaster, or CRA processing errors. Relief is discretionary and not guaranteed. The application is made using Form RC4288, and the CRA reviews each case against published criteria.

Qualifying situations typically include:

• Circumstances beyond your control (fire, flood, serious illness)
• CRA errors or delays that caused the late filing
• Financial hardship in specific, documented cases

Taxpayer relief is a last resort, not a compliance strategy. Strong bookkeeping and calendar management are far more reliable than hoping a relief application succeeds.

How to change your reporting period, register, or deregister

Changing your reporting period

If your revenue has changed and you want to switch reporting frequencies, you can request a change from the CRA. The change generally takes effect at the start of your next fiscal year. To request it:

1. Log in to CRA My Business Account and navigate to your GST/HST account.
2. Select “Change my reporting period.”
3. Confirm the new frequency and the effective date.
4. Alternatively, call the CRA Business Enquiries line at 1-800-959-5525.

Keep in mind that switching from monthly to annual reporting means you will owe a larger lump sum at year-end rather than smaller monthly remittances. Plan your cash flow accordingly.

Registering for GST/HST

When your taxable supplies exceed the $30,000 small-supplier threshold, you must register within 29 days of the supply that pushed you over. Registration is done online through CRA My Business Account or by filing Form RC1. Once registered, you must collect GST/HST on all taxable supplies from your effective registration date.

Voluntary registration is available at any time. It makes sense if you have significant business expenses and want to recover ITCs, even if your revenue is below the threshold.

Deregistering and filing a final return

If you close your business or your taxable supplies drop below the small-supplier threshold, you can apply to cancel your GST/HST registration. Here is what to complete:

• File a final GST/HST return covering the period up to your cancellation date.
• Remit any net tax owing, including ITCs you may need to repay on assets you keep after deregistration.
• Notify the CRA of your cancellation using My Business Account or Form RC145.
• Keep all GST/HST records for six years from the end of the last tax year they relate to.

The CRA will confirm your cancellation date in writing. Do not stop collecting GST/HST until you receive that confirmation.

Common filing mistakes Ontario businesses make and a compliance checklist

Ontario businesses consistently make the same handful of errors when managing GST/HST obligations. Knowing them in advance is the cheapest form of compliance.

Most common mistakes:

• Confusing the filing deadline with the payment deadline (especially for annual sole proprietors with a December 31 year-end)
• Registering late after exceeding the small-supplier threshold, which creates back-dated collection obligations
• Misclassifying exempt or zero-rated supplies as taxable, or vice versa, which distorts the net tax calculation
• Missing quarterly instalment payments and only discovering the shortfall at year-end
• Filing paper returns after the mandatory electronic-filing rule took effect in 2024

There is no separate Ontario filing. Everything goes through your federal GST/HST account, and the CRA distributes the provincial share to Ontario automatically.*

Compliance checklist for Ontario registrants:

• Set calendar reminders for every due date at least two weeks in advance
• Reconcile your GST/HST collected and ITCs monthly, even if you file quarterly or annually
• Confirm your reporting period in CRA My Business Account at the start of each fiscal year
• Authorize your accountant or bookkeeper as a CRA representative before any filing deadline
• Use CRA-certified software or My Business Account to file electronically
• Allow three business days for payment processing when remitting through a bank
• Keep invoices, receipts, and records supporting every ITC claim for six years
• Review your annual taxable supplies each year to confirm you are on the right reporting frequency

Research-backed workflows to prevent missed deadlines

The businesses that consistently file on time share one habit: they treat GST/HST reconciliation as a monthly task, not a quarterly or annual scramble. Here is a workflow that works.

1. Close your books monthly. Even quarterly filers benefit from a monthly close. Reconcile your bank accounts, accounts receivable, and accounts payable every month so your GST/HST numbers are always current.
2. Separate GST/HST collected into a dedicated account. Many Ontario small businesses hold their collected GST/HST in a separate bank account so the funds are available when remittance is due. This prevents the common problem of spending remittance funds on operations.
3. Run a GST/HST reconciliation report before every filing. Compare your accounting software’s GST/HST summary to your sales and purchase records. Discrepancies caught before filing are far easier to resolve than those caught after a CRA review.
4. Set payment reminders with lead time. Schedule your payment initiation three business days before the due date to account for bank processing. A payment initiated on the due date may arrive late.
5. Review your instalment schedule at the start of each fiscal year. If your prior-year net tax exceeded $3,000, confirm your instalment amounts and due dates in My Business Account at the beginning of the year.
6. Automate where possible. CRA My Business Account allows pre-authorized debit for GST/HST remittances. Setting this up removes the manual step of initiating each payment.

Pro Tip: If your business regularly receives GST/HST refunds rather than owing, consider electing to file monthly. The refund arrives faster, and the cash flow benefit often outweighs the administrative cost of more frequent filings. T-Ledgers can model the cash-flow impact of a frequency change for your specific situation.

Consistent bookkeeping services are the foundation of all of this. When your records are current and accurate, every GST/HST filing becomes a straightforward data-entry exercise rather than a last-minute reconstruction.

Special considerations for businesses affected by unforeseen events

Natural disasters, floods, fires, and other extraordinary events can make it physically impossible to meet a filing or payment deadline. The CRA has provisions for these situations, though they require action on your part.

The primary route is the taxpayer-relief application described in the penalties section above. For businesses in a declared disaster zone, the CRA sometimes announces blanket deadline extensions for affected regions. These announcements appear on canada.ca and are typically communicated through CRA news releases. Ontario businesses affected by events such as flooding in the Greater Toronto Area or ice storms in Eastern Ontario should monitor the CRA newsroom for any announced relief measures.

If no blanket extension applies to your situation, you can still apply for individual relief. Document everything: photographs of damage, insurance claims, correspondence with emergency services, and any evidence that the event directly prevented you from filing or paying. The stronger your documentation, the stronger your relief application.

A few practical steps if you are affected by an unforeseen event:

• File as soon as you are able, even if the deadline has passed. Late filing stops the penalty from growing further.
• Contact the CRA Business Enquiries line at 1-800-959-5525 to explain your situation and ask whether any relief measures apply.
• Submit Form RC4288 (Request for Taxpayer Relief) with your supporting documentation.
• Keep copies of all correspondence with the CRA regarding your relief request.

The CRA’s formal relief process is the correct channel for these requests. Calling the CRA to explain your circumstances is a reasonable first step, but a formal written application is what creates a record and triggers the official review.

How T-Ledgers approaches GST/HST deadlines for Ontario clients

Managing GST/HST compliance for Ontario businesses requires more than knowing the due dates. It requires a system: accurate books, a reconciliation process, and someone watching the calendar on your behalf. At T-Ledgers, the approach is to build that system around each client’s specific reporting period and fiscal year-end so that no deadline is a surprise.

Ontario clients range from sole proprietors navigating the April 30 payment and June 15 filing split for the first time, to incorporated businesses managing quarterly remittances alongside payroll and corporate tax obligations. The compliance workflow T-Ledgers uses covers monthly reconciliations, pre-filing reviews, and electronic submission through authorized CRA channels.

GST/HST filing support for Ontario businesses from T-Ledgers

Filing GST/HST returns accurately and on time is one of the most consistent compliance obligations Ontario businesses face, and the cost of getting it wrong adds up quickly. T-Ledgers offers flat-rate business tax filing and virtual CFO services that include GST/HST deadline management as part of an ongoing compliance package, with no hourly billing and no surprise invoices.

For Ontario businesses that want hands-off compliance, T-Ledgers handles:

• Calendar setup and deadline tracking — your reporting period, instalment schedule, and due dates are monitored year-round
• Electronic filing through CRA-authorized channels — returns submitted on time, with confirmation numbers retained for your records
• Instalment monitoring and remittance support — no missed quarterly payments, no end-of-year surprises

Ready to hand off your GST/HST filing? Contact T-Ledgers to get started with a flat-rate package built for your Ontario business.

Sources

The following CRA pages are the authoritative references for everything covered in this guide. Check your CRA My Business Account for personalised due dates specific to your account.

• Canada

FAQ

What is the deadline for filing a GST/HST return?

Monthly and quarterly filers must file one month after their reporting period ends. Most annual filers have three months after their fiscal year-end, though sole proprietors with a December 31 year-end can file as late as June 15.

What are the GST/HST due dates for 2026?

Due dates depend on your reporting frequency. A quarterly filer’s Q1 2026 return (January–March) is due April 30, 2026. An annual filer with a December 31, 2025 year-end must file by March 31, 2026, or June 15, 2026 if they are a sole proprietor with business income.

What happens if I miss a GST/HST filing deadline?

Filing immediately, even without payment, stops the penalty from growing further.

Do I have to file GST/HST electronically in 2026?

Yes. For reporting periods beginning in 2024 and later, electronic filing is mandatory for most registrants. Charities and selected listed financial institutions are exempt. Filing on paper when e-filing is required carries a penalty of $100 for the first offence and $250 for each subsequent paper return.

Can T-Ledgers manage my GST/HST filing deadlines?

Yes. T-Ledgers provides flat-rate GST/HST filing and deadline management for Ontario businesses, including calendar setup, electronic submission, and instalment monitoring. Contact T-Ledgers to discuss a package suited to your reporting period and business size.

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