Insights
Nov 12, 2025
Mackisen
GST/QST Filing for Businesses: 10-Step Checklist for a Smooth Return — Montreal CPA Firm Near You
Introduction
Filing GST (Goods and Services Tax) and QST (Quebec Sales Tax) accurately and on time is essential for every Quebec business. Whether you’re a startup, small retailer, or service-based company, following a structured process prevents costly errors, penalties, and cash flow stress.
At Mackisen CPA Montreal, we’ve created this 10-step checklist to help business owners prepare, calculate, and file their GST/QST returns smoothly — ensuring full compliance with Revenu Québec (ARQ) and the Canada Revenue Agency (CRA).
Step 1: Verify Your Registration and Filing Frequency
Before filing, confirm that:
Your business is properly registered for both GST (with CRA) and QST (with ARQ).
You know your reporting frequency — monthly, quarterly, or annually — based on your sales:
Under $1.5M: Annual filing.
$1.5M–$6M: Quarterly filing.
Over $6M: Monthly filing.
You’ve noted your filing deadlines and added reminders to your calendar.
Mackisen Tip: Late filing results in a 5% penalty plus 1% per month (max 12 months).
Step 2: Collect All Sales Records
Gather all documents showing taxable sales for the period:
Sales invoices and receipts.
POS or e-commerce reports (Shopify, Square, Lightspeed).
Bank statements showing customer deposits.
Export sales (0% rated) and exempt transactions (e.g., residential rent).
Verify:
All invoices include your GST (RT) and QST (TQ) registration numbers.
GST (5%) and QST (9.975%) were applied correctly.
Step 3: Collect All Purchase and Expense Records
Gather all supporting documents for business purchases and expenses:
Supplier invoices and receipts.
Credit card statements or online receipts.
Bills for rent, utilities, and services.
Each invoice must show:
The supplier’s GST and QST registration numbers.
The amount of GST/QST paid.
These will be used to calculate Input Tax Credits (ITCs) and Input Tax Refunds (ITRs).
Step 4: Reconcile Your Accounts
Before filing, reconcile:
Sales vs. deposits (to confirm all income was declared).
Purchases vs. payments (to ensure expenses match invoices).
GST/QST collected vs. payable (from your accounting system).
If you use software like QuickBooks, Sage, or Xero, generate:
GST/HST Summary Report.
QST Summary (FPZ-500-V compatible).
Reconciliation ensures your return matches your actual activity and prevents audit triggers.
Step 5: Calculate Taxes Collected
Compute the total GST and QST you charged customers during the filing period.
Example:
Sales before taxes = $100,000
GST (5%) = $5,000
QST (9.975%) = ($100,000 + $5,000) × 9.975% = $10,474
Total taxes collected = $15,474
Step 6: Calculate Input Tax Credits (ITCs) and Input Tax Refunds (ITRs)
Add up all eligible GST and QST paid on business expenses:
Rent and utilities.
Equipment and supplies.
Professional fees.
Subcontractor services.
Example:
GST paid = $3,200
QST paid = $6,400
Total ITCs/ITRs = $9,600
Ensure all expenses are for commercial use — personal or non-business expenses are not eligible.
Step 7: Determine Net Tax Payable or Refundable
Formula:
(GST + QST collected) – (GST + QST paid on purchases) = Net tax payable or refund
Example:
Taxes collected = $15,474
Taxes paid = $9,600
Net tax to remit = $5,874
If the result is negative, you’ll receive a refund instead.
Step 8: File Your Returns Electronically
A. GST/HST (CRA)
File through My Business Account:http://canada.ca/my-business-account.
Use Form GST34 (or GST62 for paper filing).
B. QST (Revenu Québec)
File through Mon Dossier pour les entreprises: http://revenuquebec.ca/mon-dossier.
Use Form FPZ-500-V if filing manually.
Always save electronic confirmation numbers and filing receipts.
Step 9: Make Your Payment or Confirm Refund
Payment:
Pay electronically via online banking (“CRA GST/HST” or “Revenu Québec – TVQ”).
Or use pre-authorized debit in your online account.
Refunds:
CRA and Revenu Québec usually issue refunds within 10–15 business days (if filed online).
Confirm via your account dashboards.
Pro Tip: Transfer collected GST/QST to a separate bank account during the year so payment is effortless.
Step 10: Keep Records and Prepare for Audits
Keep all GST/QST records for at least six years under Tax Administration Act s.34:
Sales and purchase invoices.
Filing confirmations.
Bank and POS reports.
Supplier registration proofs.
Audit readiness checklist:
☑ All supplier invoices have valid GST/QST numbers.
☑ Totals reconcile to accounting system.
☑ Refunds or credits are supported by documentation.
At Mackisen CPA Montreal, we create Audit-Ready Tax Binders for clients — digital or paper — to protect them during CRA or Revenu Québec reviews.
Jurisprudence and Legal Insight
Canadian courts emphasize that businesses, not accountants, are legally responsible for accurate filings:
Hickman Motors Ltd. v. Canada (SCC 1997) — taxpayers must prove compliance.
Canderel Ltd. v. Canada (SCC 1998) — filings must reflect true commercial reality.
Lac d’Amiante du Québec Ltée (SCC 2001) — Revenu Québec has the right to demand full documentation.
Proper records are your best legal defense.
Winning With CRA and Revenu Québec
At Mackisen CPA Montreal, we ensure every client’s filing process is smooth, accurate, and audit-proof:
Data Verification – We check every invoice and receipt for compliance.
Tax Reconciliation – We balance GST/QST accounts before submission.
Electronic Filing – We handle both CRA and ARQ filings on time.
Documentation – We build audit-ready records.
Penalty Protection – We help clients apply for relief under s.94.1 if needed.
Mackisen Service Hub: Simplified Filing & Compliance
Our Mackisen Service Hub provides turnkey GST/QST support:
Registration and setup.
Monthly/quarterly filings and payments.
Refund optimization and documentation tracking.
Audit representation and compliance training.
Our bilingual team — CPA auditors, tax lawyers, and compliance specialists from McGill, Université de Montréal, and Concordia University — delivers precision, compliance, and peace of mind.
Real Client Example
A Laval marketing agency failed to reconcile its QST reports correctly and faced a $9,000 reassessment. Mackisen CPA rebuilt their quarterly reports, corrected filings retroactively, and automated their GST/QST workflows. The agency now files in under 30 minutes per quarter with zero errors.
Why Mackisen
With over 35 years of combined CPA and legal expertise, Mackisen CPA Montreal ensures your GST/QST returns are filed accurately, on time, and fully supported by documentation.
When you file with Mackisen, every line is verified, every credit is claimed, and every return is stress-free — from the first calculation to the final confirmation.
