What’s the Deadline to Remit GST/QST Payments After Filing?

Filing your GST/QST return is only half of the compliance requirement the payment must also be made on time. Many Quebec businesses believe that filing the return on the deadline automatically means they are compliant, but Revenu Québec imposes penalties and interest if the payment arrives even one day late. Understanding the remittance deadline is essential for avoiding unnecessary charges and protecting your refund eligibility.

This guide explains exactly when GST/QST payments are due, how deadlines differ by filing frequency, and what happens if you pay late.

Filing vs. Payment: Two Separate Obligations

Every GST/QST period has two obligations:

1. File the return (FPZ-500-V)

2. Pay the balance owing

Even if you file on time, a late payment still triggers:
• daily interest
• potential penalties
• frozen refunds

Payment Deadlines by Filing Frequency

1. Monthly Filers

Payment is due the last day of the following month.

Example:
January period → payment due February 28/29

2. Quarterly Filers

Payment is due the last day of the month following the quarter.

Examples:
Q1 (Jan–Mar) → April 30
Q2 (Apr–Jun) → July 31
Q3 (Jul–Sep) → October 31
Q4 (Oct–Dec) → January 31

3. Annual Filers

Payment is due three months after fiscal year-end.

Example:
December 31 year-end → payment due March 31

Important:
Self-employed individuals often confuse this with personal tax rules but GST/QST must be paid within 3 months, not 4.

What Happens If You Pay Late?

If you miss the remittance deadline:

1. Interest Starts the Very Next Day

Interest is applied daily, compounded, and cannot be waived except in exceptional circumstances.

2. Penalties May Apply

• late filing penalties (if return was late)
• late payment penalties (if payment was late)
• repeated failure penalties for chronic lateness

3. Refunds Are Frozen

Revenu Québec will:
• hold your refund
• apply the refund to outstanding balances
• delay release until your account is compliant

4. Your Account Gets Flagged

Repeated late payments increase the risk of:
• verification reviews
• audit selection
• additional correspondence

Different Payment Methods Have Different Timelines

1. Online banking (most reliable)

Considered paid on the date the transaction is submitted.

2. Pre-authorized debit through My Account

Safe and automatic but must be set up before the deadline.

3. Cheques (not recommended)

• must arrive before the deadline
• postal delays do not excuse late payment

4. Payments at financial institutions

Must be timestamped by the due date.

What If You Can’t Pay Immediately?

Revenu Québec allows:
• payment arrangements
• scheduled installment plans
• short-term relief requests

But interest still accrues until the balance is paid.

How to Avoid Missing Deadlines

• set reminders in your calendar
• reconcile GST/QST monthly
• use accounting software with tax alerts
• automate payments when possible
• verify balances before the due date
• avoid filing on the final day
• keep extra cash for tax remittances

Mackisen Strategy

Mackisen CPA helps businesses:
• prepare accurate GST/QST returns
• calculate the correct balance owing
• set up reliable remittance procedures
• manage cash flow for tax payments
• negotiate payment arrangements when needed
• avoid penalties with proactive filing systems

Real Client Experience

A retailer filed GST/QST on time but paid 48 hours late interest accumulated and a refund was frozen. Mackisen corrected future systems.

A consultant forgot quarterly payments for two periods. Mackisen arranged a payment plan and removed penalties.

A startup misunderstood the annual payment rule. Mackisen fixed the deadline and prevented costly interest buildup.

Common Questions

Is filing enough to avoid penalties?
No filing without payment still triggers interest.

Does Revenu Québec give grace periods?
No deadlines are strict.

Can my refund be taken if I owe money?
Yes refunds are automatically applied to outstanding balances.

Why Mackisen

With more than 35 years of combined CPA experience, Mackisen CPA Montreal helps businesses stay on track with GST/QST filing and payment deadlines, preventing penalties and keeping your account in perfect standing.