This article is for informational purposes only and does not constitute tax or financial advice. Consult a qualified accounting professional before making any tax or financial decisions.
Quick answer: your remaining 2026 installment dates
The two remaining 2026 CRA personal tax installment payments are due Tuesday, September 15, 2026, and Tuesday, December 15, 2026. You are required to pay installments only if your net tax owing is more than $3,000 for 2026 and was also more than $3,000 in either 2025 or 2024 (Quebec residents use an $1,800 threshold). The CRA August reminder (form INNS1) lists your suggested payment amounts, and you may choose the no-calculation, prior-year, or current-year option. Paying the amounts on the reminder in full by each due date is the safest way to avoid installment interest and the 50% penalty that applies when annual installment interest exceeds $1,000.
Why the September and December installments matter this year
Two 2026 dates are still ahead of you: September 15 and December 15. If the Canada Revenue Agency (CRA) sent you an installment reminder in August, or if 2026 is the first year your income has outrun the tax withheld from it, you have a decision to make.
The pressure is greater than usual this year. 2026 brought updated federal tax brackets, benefit-payment changes, and shifting employer withholding, so the amount CRA suggested in February may no longer match what you will actually owe. Recalculating now is often the difference between a smooth December filing and a spring surprise.
This guide covers the two remaining dates, who has to pay, how to pick the safest calculation method, and what happens if you miss a payment. Compare against the 2026 personal tax brackets if your income has moved this year.
Quick Start: pick your path
Find your situation in the list below.
- →Salaried employee with a small side income: installments are unlikely to be required. Confirm by checking whether your 2025 net tax owing exceeded $3,000.
- →Sole proprietor or freelancer: installments are common. Review the sole proprietor tax deductions that reduce net tax before you calculate.
- →Incorporated professional taking dividends: personal installments apply on the dividend income; corporate installments follow separate rules.
- →Retiree drawing RRIF or LIF income: installments are common when withholding is set to the CRA minimum.
- →Landlord or investor: unshielded capital gains and rental profit can push you across the threshold quickly.
Look up your INNS1 reminder in CRA My Account before you calculate anything. The amount CRA has already suggested is your simplest safe path.
Who has to pay installments in 2026
The province where you live on December 31, 2026 sets the threshold. Quebec residents use $1,800; everyone else uses $3,000. Because CRA compares your projected 2026 net tax owing against one of the two prior years, a single spike year usually does not force installments the next year. Two back-to-back years above the threshold typically do.
Farmers and fishers whose main source of income is farming or fishing self-employment follow a different rule: a single installment due date of December 31, 2026. Everyone else uses the four quarterly dates.
If you receive an installment reminder (form INNS1) in August but you now expect your 2026 net tax owing to be $3,000 or less ($1,800 or less in Quebec), you may reduce or skip the September and December payments. CRA generally will not charge installment interest in that situation.
Comparing the three CRA calculation options
CRA gives you three ways to arrive at each installment amount. The choice determines both what you pay and how much installment interest you may owe.
The no-calculation option is what CRA prints on your INNS1 reminder. CRA works out the numbers based on your 2024 and 2025 tax returns. Paying these amounts in full by every due date typically guarantees no installment interest, regardless of how your 2026 income turns out. This is the safest option and the one most Ontario taxpayers use.
The prior-year option uses your 2025 net tax owing (plus any Canada Pension Plan contributions payable and voluntary Employment Insurance premiums) divided into equal payments. It works well when your 2026 income looks similar to 2025. Like the no-calculation option, it protects you from installment interest as long as you pay in full and on time.
The current-year option uses your estimated 2026 net tax owing divided into equal payments. It produces the lowest payment if your income has dropped year over year, but it also carries the highest risk: if you underestimate, CRA charges installment interest on the shortfall.
An important twist applies when you receive only an August reminder. If your reminder does not list a March or June payment and you choose the prior-year or current-year option, CRA requires 75% of the annual total on September 15 and 25% on December 15 — not two equal payments.
Your step-by-step September 15 and December 15 roadmap
- 1Find your INNS1 in CRA My AccountThe August reminder is called form INNS1 and arrives by mail or in your CRA My Account under Mail. It lists suggested payment amounts alongside all three calculation options. See our guide on using your CRA account if you have not signed in recently.
- 2Compare your 2026 income to your 2025 returnPull your 2025 Notice of Assessment for the net tax owing figure. If your 2026 income has stayed roughly the same, the no-calculation option on the INNS1 is almost always the right choice.
- 3Run the current-year option only if your income droppedProject your total 2026 income, subtract expected deductions and credits, apply the federal and Ontario tax rates, and subtract any tax already withheld. Because underestimating triggers installment interest, most taxpayers add a modest buffer.
- 4Schedule the payment through online bankingAdd “CRA (revenue) – 2026 tax installment” as a payee and use your Social Insurance Number as the account number. CRA My Payment and pre-authorized debit through My Account also work; mail and in-person payment take longer and rely on receipt-date rules.
- 5Pay a few business days before the due dateSave the confirmation number. Payments received after the due date are treated as late even if you sent them earlier.
What happens if you miss the September 15 or December 15 payment
The prescribed rate for overdue amounts changes each calendar quarter and has been noticeably higher than typical bank rates through 2025 and 2026. Because the interest compounds daily, a missed September payment continues to grow through the December date and beyond. Learn more about how to recover after a missed CRA deadline.
Two things soften the impact. First, if you overpaid an earlier installment, CRA applies that contra credit against interest that would otherwise accrue on a later missed payment in the same year. Second, catching up as quickly as possible reduces both the interest and the risk of crossing the $1,000 penalty threshold. If you know a payment will be late, do not skip it — pay whatever you can on time and remit the balance as soon as possible.
Common installment mistakes to avoid
Ontario taxpayers repeatedly stumble on the same handful of issues. Each of these typically results in avoidable installment interest and, in worse cases, the 50% penalty tier.
- →Assuming the CRA installment reminder is optional. Reminders are the CRA's way of telling you the rule applies to you. Ignoring one does not exempt you from installment interest.
- →Splitting the August-only reminder into two equal payments. When only the August reminder is issued, the prior-year and current-year options require 75% on September 15 and 25% on December 15.
- →Waiting until December to true up. Any shortfall on the September payment continues to compound at the prescribed rate for three more months.
- →Using the current-year option without a buffer. Underestimating 2026 income by even a few thousand dollars can trigger installment interest.
- →Paying the balance owing on April 30 instead of the installment on December 15. April 30 is the balance-due date for your return, not an installment date.
- →Forgetting the Quebec threshold rule. Residents of Quebec on December 31 use an $1,800 net-tax-owing test, not $3,000.
Frequently asked questions
When exactly are my 2026 tax installment payments due?
Do I have to pay a September 15 installment if I only got a reminder in August?
What if my income has dropped in 2026 — can I pay less?
What is the CRA's no-calculation option, and is it always safe?
How does the CRA charge interest if I miss the September 15 or December 15 payment?
Can I skip the December 15 installment if I overpaid in September?
Do the same installment rules apply to a corporation or just to me personally?
What if I never received an installment reminder — do I still owe one?
Ready to lock in your September and December payments?
If you would like a second set of eyes on your INNS1 amounts, or if your situation has changed, ClearWealth Accounting Advisors can help. Our team plans installments as part of a full year-round tax strategy for Ontario individuals and SMEs.
Book a ConsultationSources & References
- Canada Revenue Agency — Payment due dates for installments: canada.ca
- Canada Revenue Agency — Who has to pay income tax by installments: canada.ca
- Canada Revenue Agency — Required tax installments for individuals: canada.ca
- Canada Revenue Agency — Prescribed interest rates (2026 Q3): canada.ca
- Canada Revenue Agency — Instalment interest and penalty: canada.ca
