Upcoming CRA Tax Deadlines in Canada: September–December 2026

Stay ahead of your CRA filing and payment deadlines. For Canadian business owners, self-employed individuals, and employers, missing a tax deadline can lead to interest, penalties, and unnecessary cash-flow pressure.

With the final months of 2026 approaching, now is a good time to review your GST/HST, payroll, personal tax instalments, and corporate tax obligations.

Important: CRA deadlines depend on your reporting period, remitter type, fiscal year-end, and individual circumstances. The dates below are common deadlines and should not be treated as a substitute for checking your CRA account or specific filing requirements.

Key CRA Deadlines Coming Up in 2026

DateDeadlineWho It May Apply ToSeptember 30, 2026GST/HST return & paymentMonthly GST/HST filers for AugustOctober 15, 2026Payroll remittanceEmployers with a September remittance due on this date, including eligible quarterly remittersOctober 31, 2026GST/HST quarterly deadlineQuarterly filers with a July–September reporting period; because Oct. 31 is Saturday, the deadline moves to the next business dayDecember 15, 2026Personal tax instalmentIndividuals required to make quarterly instalmentsDecember 31, 2026Corporate instalment / other tax obligationsDepends on corporation's fiscal year and instalment schedule

Let's look at each deadline in more detail.

1. September 30, 2026 — GST/HST Filing and Payment

If you are a monthly GST/HST filer, your return and payment are generally due one month after the end of your reporting period.

For example:

August 2026 reporting period → September 30, 2026 deadline

You generally need to:

• Complete your GST/HST return

• Report GST/HST collected

• Claim eligible input tax credits (ITCs)

• Determine your net GST/HST

• File the return

• Pay any balance owing

CRA confirms that monthly and quarterly GST/HST returns are generally due one month after the end of the reporting period. If a deadline falls on a weekend or CRA-recognized public holiday, the return or payment is generally considered on time when received on the next business day.

Don't forget about ITCs

One of the most common GST/HST mistakes for small businesses is failing to properly track input tax credits.

Your bookkeeping should clearly identify:

• GST/HST collected on sales

• GST/HST paid on business expenses

• Eligible ITCs

• Exempt or zero-rated transactions

• Personal portions of expenses

• Adjustments and prior-period corrections

A GST/HST return should be prepared from properly reconciled accounting records—not simply from the bank balance.

2. October 15, 2026 — Payroll Remittance Deadline

If you have employees, your payroll obligations don't end when you run payroll.

You may also have to remit amounts withheld from employee pay, including:

• Income tax

• CPP contributions

• EI premiums

Your exact payroll remittance deadline depends on your CRA remitter type.

Regular remitters

For a regular remitter, CRA generally requires deductions to be received by the 15th day of the following month.

Therefore, payroll deductions from September may have a October 15, 2026 remittance deadline.

Quarterly remitters

Eligible small employers may remit payroll deductions quarterly.

For July–September, the quarterly remittance deadline is October 15, 2026.

Important: Not every employer has the same deadline

Employers can have different remittance schedules, including:

• Regular

• Quarterly

• Accelerated remitter 1

• Accelerated remitter 2

Your remitter type can significantly change your deadline. CRA recommends checking your payroll account to confirm your remittance requirements.

3. October 31, 2026 — Quarterly GST/HST Deadline

For a business with a July 1–September 30 quarterly reporting period, the normal GST/HST filing and payment deadline is one month after the end of the quarter:

October 31, 2026

However, October 31, 2026 falls on a Saturday.

CRA's weekend rule means the deadline moves to the next business day, which is November 2, 2026, assuming no CRA-recognized public holiday affects the date.

What should you have ready?

Before filing your quarterly GST/HST return, review:

• Sales revenue

• GST/HST collected

• Business purchases

• ITCs

• Credit card transactions

• Vehicle expenses

• Subcontractor expenses

• Receipts and invoices

• Bank reconciliations

• Previous GST/HST balances

A last-minute GST/HST calculation can create avoidable errors—especially when bookkeeping hasn't been reconciled throughout the quarter.

4. December 15, 2026 — Personal Tax Instalment

December 15 is particularly important for self-employed individuals and other taxpayers who are required to pay income tax by instalments.

The standard quarterly instalment dates for individuals are:

• March 15

• June 15

• September 15

• December 15

CRA states that individuals may have to make instalment payments when their net tax owing exceeds the applicable threshold and they also had sufficient net tax owing in one of the preceding years. For 2026, the general threshold is more than $3,000 outside Quebec.

This can be particularly relevant to:

• Sole proprietors

• Self-employed professionals

• Contractors

• Realtors

• Commission-based workers

• Individuals with significant investment income

• Others who don't have enough tax withheld at source

Can you simply pay the amount CRA suggests?

Not necessarily.

CRA provides different calculation methods, including:

1. No-calculation method

2. Prior-year method

3. Current-year method

The appropriate method can depend on how your 2026 income compares with previous years.

If your income has changed significantly, it may be worth reviewing your expected 2026 tax liability rather than blindly relying on an instalment amount.

5. December 31, 2026 — Corporate Tax Instalments

Corporate tax instalments work differently from personal tax instalments.

There is no universal December 31 corporate tax deadline for every corporation.

Corporate instalment dates depend on:

• Your corporation's fiscal year

• Whether you pay monthly or quarterly

• Whether your corporation qualifies for quarterly instalments

• Your tax payable

Generally, corporations make instalments on the last day of each complete month of their tax year. Eligible small CCPCs may qualify to pay quarterly instead.

For example, a calendar-year corporation eligible for quarterly instalments generally has instalments due:

• March 31

• June 30

• September 30

• December 31

But corporations with different year-ends can have completely different dates.

What About Corporate Tax Balances?

Don't confuse corporate tax instalments with the final corporate tax payment.

Generally, corporate tax is due two months after the end of the tax year.

Certain CCPCs can qualify for a three-month balance-due date if the CRA conditions are met.

For example, a December 31 year-end corporation may have a balance-due date in:

February or March of the following year, depending on its eligibility.

The T2 Corporation Income Tax Return itself is generally due six months after the corporation's year-end, even though the tax payment deadline can be earlier.

Don't Forget T4, T4A and T5018 Deadlines

Not every important CRA deadline happens in September or December.

T4 and T4A

For businesses with employees or certain other payment obligations, T4, T4A, T4A-NR and T4A-RCA information returns are generally due by the last day of February following the calendar year.

For the 2026 calendar year, that means the normal deadline will be in February 2027.

T5018

Businesses in the construction industry that are required to report subcontractor payments have a different deadline.

The CRA generally requires T5018 information returns six months after the end of the reporting period chosen by the payer.

For a calendar-year reporting period ending December 31, that generally means June 30 of the following year.

A Simple Year-End Tax Checklist for Business Owners

Before the end of 2026, consider reviewing:

GST/HST

☐ Reconcile GST/HST collected
☐ Reconcile ITCs
☐ Review outstanding invoices
☐ Review GST/HST account with CRA
☐ Confirm your filing frequency

Payroll

☐ Confirm CRA remitter type
☐ Reconcile payroll clearing accounts
☐ Confirm payroll remittances
☐ Review employee benefits and taxable benefits
☐ Prepare for T4 reporting

Corporate Tax

☐ Review corporate instalments
☐ Estimate current-year taxable income
☐ Review expenses and capital purchases
☐ Review shareholder transactions
☐ Reconcile shareholder loans
☐ Review year-end tax planning opportunities

Personal Tax

☐ Review December tax instalment
☐ Estimate personal taxable income
☐ Review RRSP/FHSA opportunities where applicable
☐ Review investment income
☐ Keep business and personal expenses separate

What Happens If You Miss a CRA Deadline?

Depending on the type of obligation, missing a deadline can result in:

• Interest

• Late-filing penalties

• Late-payment penalties

• Instalment interest

• Additional CRA correspondence

• Cash-flow pressure

For example, CRA states that late or insufficient personal tax instalments can result in instalment interest and possible penalties.

The cost of a missed deadline isn't always limited to the original tax amount.

Final Takeaway

Don't wait until the CRA deadline to start looking at your numbers.

For business owners, the best approach is to maintain your bookkeeping throughout the year, reconcile your GST/HST and payroll accounts regularly, monitor CRA balances, and review upcoming instalments before they're due.

If your income or business activity has changed significantly during 2026, your tax obligations may also change. A year-end review can help identify potential issues before they become expensive surprises.

Need help staying on top of your accounting and tax deadlines?

CPA Charanpreet Singh provides accounting, bookkeeping, tax, payroll, GST/HST and business advisory services for owner-managed businesses in Kitchener, Waterloo, Cambridge and across Ontario.

Book a consultation to review your accounting and tax obligations.

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© 2026 CPA Charanpreet Singh