A GST/QST Filing Success Story

A Montreal entrepreneur came to Mackisen overwhelmed, behind on filings, and facing multiple warning letters from Revenu Québec. Missing receipts, incorrect GST/QST coding, and months of unreconciled bank activity created a chain reaction of problems. What looked like a hopeless situation turned into a complete compliance recovery and the business ended up fully caught up, refund-positive, and audit-ready.

This case study shows how Mackisen transformed total chaos into clean, reliable, government-approved compliance.

The Situation: Months (or Years) of Behind Filings

The business had accumulated:
• several unfiled GST/QST periods
• missing invoices and receipts
• no bank reconciliation for up to 10 months
• e-commerce sales not matched to deposits
• personal transactions mixed into business accounts
• incorrect GST/QST setup inside the accounting software

Revenu Québec had already:
• frozen expected refunds
• issued multiple reminder notices
• threatened assessments for missing periods

The business owner feared penalties, interest, and a possible audit.

The Challenges Identified

Mackisen’s team discovered:
• hundreds of uncategorized transactions
• missing ITC/ITR documentation
• wrong tax codes applied to many entries
• inaccurate sales totals due to duplicated transactions
• software subscriptions not downloaded or recorded
• deposits not tied to invoices, appearing as unexplained revenue

Without a complete reconstruction, the business risked thousands in reassessments.

Step-by-Step: How Mackisen Restored Compliance

Step 1 — Full Bookkeeping Reconstruction

The team:
• downloaded all banking, credit card, and PayPal/Stripe data
• rebuilt accurate sales and expense records
• separated personal vs business transactions
• categorized every payment and deposit
• recalculated proper GST/QST amounts

This created a clean financial foundation.

Step 2 — Rebuilding Missing Documentation

Mackisen collected:
• supplier invoices
• monthly SaaS receipts
• equipment purchase records
• subcontractor and consulting invoices
• proof of payment for all large expenses

A complete ITC/ITR support package was prepared for each period.

Step 3 — Correcting GST/QST Coding

The accounting file was fixed to:
• apply correct GST (5%)
• apply correct QST (9.975%)
• separate zero-rated and exempt items
• remove tax from personal expenses
• fix duplicated ITC/ITR claims

Future filings became accurate and automatic.

Step 4 — Filing All Missing Periods

Mackisen filed:
• multiple monthly or quarterly returns
• corrected prior-year returns
• adjustment entries for misclassified expenses

Each return included proper documentation to avoid verification delays.

Step 5 — Communication With Revenu Québec

The CPA team:
• informed Revenu Québec of the cleanup in progress
• responded to every letter
• prevented assessments
• secured the release of refund holds

This stabilized the business’s tax account immediately.

The Outcome

The business:
• caught up on every GST/QST period
• received several quarters of refunds
• avoided penalties for late filing
• avoided interest charges on estimated assessments
• established perfect compliance going forward
• gained an accounting system ready for audit at any time

The owner went from overwhelmed to fully in control.

Key Lessons

• Falling behind is common but fixable
• Reconstruction is possible, even for multiple years
• Refunds can be recovered when documentation is rebuilt
• GST/QST coding errors are a major cause of filing problems
• Proper monthly bookkeeping prevents compliance disasters

Real Client Quote

“I thought my situation was impossible. Mackisen organized everything, filed everything, and got my refunds released. I finally sleep at night.”

Common Questions

Can I fix years of missing GST/QST returns?
Yes reconstruction and adjustments are routine.

Will I automatically get penalties?
Not if handled proactively and professionally.

What if I lost receipts?
Duplicates can often be obtained or alternative documentation used.

Can I still get refunds even if behind?
Yes once filings are corrected and complete.

Why Mackisen

With more than 35 years of combined CPA experience, Mackisen CPA Montreal specializes in cleaning up messy GST/QST files, rebuilding books, and ensuring long-term compliance. No matter how chaotic your file seems, we can fix it quickly and professionally.