Why This Calculator Exists
Most Canadian merchants have no idea what they're actually paying. Your processor shows you a rate — 2.9% + $0.30, or "interchange-plus 0.20%" — but the real cost depends on your card mix, transaction size, and whether you're processing in-person or online.
The biggest hidden savings? Interac debit.
Every Interac tap costs you roughly $0.07. That same transaction on a Visa Infinite card costs 1.58% + markup.
On a $50 purchase, that's $0.07 vs $0.95. A restaurant doing $20K/month with 40% debit is leaving real money on the table with flat-rate pricing.
Flat-Rate vs Interchange-Plus: The Real Math
Stripe and Square charge 2.9% + $0.30 online and 2.65–2.7% in-person regardless of card type. That means you pay the same rate on an Interac debit tap ($0.06 interchange) as a World Elite Mastercard (2.04% interchange).
At low volume, the simplicity is worth it. At $10K+/month, you're typically overpaying by $100–$400/month compared to Helcim's interchange-plus pricing. The breakeven point depends on your debit percentage — the more debit you process, the more flat-rate hurts.
The 2024/2025 Small Business Interchange Reduction
The federal government pressured Visa and Mastercard to reduce interchange for small businesses. If your annual Visa volume is under $300K or Mastercard under $175K, you qualify for rates roughly 27% lower than standard interchange.
Here's the catch: if you're on flat-rate pricing (Stripe, Square), you see zero benefit. They charge 2.9% regardless.
The savings only flow through on interchange-plus pricing. The Canadian Federation of Independent Business (CFIB) specifically called out Stripe for pocketing these reductions. See our guide on finding the cheapest processing rates.
When Flat-Rate Actually Wins
Flat-rate isn't always worse. If you process mostly online, mostly credit (low debit %), and your average transaction is small (under $15), flat-rate can be competitive. The $0.30 per-transaction fee on interchange-plus adds up fast on small tickets.
Coffee shops doing $4 lattes on Stripe pay 2.9% + $0.30 = $0.42 per transaction (effective rate: 10.5%). That's terrible.
But switching to interchange-plus with a $0.08 per-transaction fee gives you ~1.5% + $0.08 = $0.14 (3.5% effective). For small tickets, the per-transaction fee matters more than the percentage.