Cross the 15% Down Payment Line in Canada and Cut Your CMHC Premium by Thousands
A $525,000 condo in Mississauga required a $78,750 down payment to hit exactly 15%. The buyers had $73,125 saved, just under 14%, and planned to close with that. Their broker ran the numbers twice: once at their current amount, once at the 15% line. The difference in mortgage insurance premium alone was $1,335. That's how much extra they would pay, financed into the loan and carried with interest, by stopping $5,625 short.
The Step-Function Problem
Mortgage insurance in Canada isn't a sliding scale. It's a hard step. From 10% down to 14.99% down, CMHC charges 3.10% of the loan amount as a premium. At exactly 15%, the rate drops to 2.80%. On a $450,000 loan, that 0.30 percentage point spread costs $1,350 upfront, plus the interest you'll pay on that amount over 25 years. Cross $75,000 on a $500,000 purchase and you cut the premium rate by nearly 10%. Miss it by $500 and you pay full freight.
The premium tiers lock at specific thresholds: 5%, 10%, 15%, 20%. The jump from 5% to 10% saves you 0.90 percentage points. From 10% to 15%, you save 0.30 points. The marginal return shrinks as you climb, but each threshold is binary. You're either over or you're not.
Where the Extra Cash Comes From
Most buyers who land $2,000 short of a tier didn't budget for it. The money shows up from elsewhere. A parent writes a gift letter for $5,000 and the buyers deposit it two weeks before closing, which moves them from 14.8% to 15.2%. Someone cashes out a small non-registered investment account they'd forgotten about. Another client had $8,000 sitting in a TFSA earning 4%; moving it into the down payment saved them $1,800 in insurance premiums and effectively returned 22% in one transaction.
The opportunity-cost math matters here. If you're pulling $5,000 from an emergency fund that drops you below three months of expenses, the premium savings don't outweigh the risk of a cash shortfall. If you're borrowing on a credit card at 21% to top up the deposit, you've just made the problem worse. But if the extra amount comes from a low-yield savings account, a non-registered GIC near maturity, or a family gift that was coming anyway, the return is immediate and locked in for the life of the mortgage.
The PST Trap
Ontario charges 8% provincial sales tax on the insurance premium. Quebec charges 9%. That tax is due at closing, in cash, and cannot be financed. On a $450,000 loan at the 3.10% tier, the premium is $13,950. Ontario PST adds another $1,116 that must be wired to the lawyer the day you take possession. Drop the premium to 2.80% by crossing 15%, and the PST bill falls to $1,008. You've just freed up $108 in closing-day cash, on top of the $1,350 in financed premium you no longer carry.
Lenders typically focus on whether you qualify at all, rather than which tier you land in. A buyer stretched to afford 12% down isn't told that finding another 3% would cut their insurance cost by thousands. The qualification is the gate; what you do with the remaining down payment choices is left to the buyer.
The clearest signal that you should push for the next tier: when the incremental cash required is less than one third of the premium savings. At that ratio, you're effectively earning a triple-digit return on money you deploy once.
A $525,000 condo in Mississauga required a $78,750 down payment to hit exactly 15%. The buyers had $73,125 saved, just under 14%, and planned to close with that. Their broker ran the numbers twice: once at their current amount, once at the 15% line. The difference in mortgage insurance premium alone was $1,335. That's how much extra they would pay, financed into the loan and carried with interest, by stopping $5,625 short.
The Step-Function Problem
Mortgage insurance in Canada isn't a sliding scale. It's a hard step. From 10% down to 14.99% down, CMHC charges 3.10% of the loan amount as a premium. At exactly 15%, the rate drops to 2.80%. On a $450,000 loan, that 0.30 percentage point spread costs $1,350 upfront, plus the interest you'll pay on that amount over 25 years. Cross $75,000 on a $500,000 purchase and you cut the premium rate by nearly 10%. Miss it by $500 and you pay full freight.
The premium tiers lock at specific thresholds: 5%, 10%, 15%, 20%. The jump from 5% to 10% saves you 0.90 percentage points. From 10% to 15%, you save 0.30 points. The marginal return shrinks as you climb, but each threshold is binary. You're either over or you're not.
Where the Extra Cash Comes From
Most buyers who land $2,000 short of a tier didn't budget for it. The money shows up from elsewhere. A parent writes a gift letter for $5,000 and the buyers deposit it two weeks before closing, which moves them from 14.8% to 15.2%. Someone cashes out a small non-registered investment account they'd forgotten about. Another client had $8,000 sitting in a TFSA earning 4%; moving it into the down payment saved them $1,800 in insurance premiums and effectively returned 22% in one transaction.
The opportunity-cost math matters here. If you're pulling $5,000 from an emergency fund that drops you below three months of expenses, the premium savings don't outweigh the risk of a cash shortfall. If you're borrowing on a credit card at 21% to top up the deposit, you've just made the problem worse. But if the extra amount comes from a low-yield savings account, a non-registered GIC near maturity, or a family gift that was coming anyway, the return is immediate and locked in for the life of the mortgage.
The PST Trap
Ontario charges 8% provincial sales tax on the insurance premium. Quebec charges 9%. That tax is due at closing, in cash, and cannot be financed. On a $450,000 loan at the 3.10% tier, the premium is $13,950. Ontario PST adds another $1,116 that must be wired to the lawyer the day you take possession. Drop the premium to 2.80% by crossing 15%, and the PST bill falls to $1,008. You've just freed up $108 in closing-day cash, on top of the $1,350 in financed premium you no longer carry.
Lenders typically focus on whether you qualify at all, rather than which tier you land in. A buyer stretched to afford 12% down isn't told that finding another 3% would cut their insurance cost by thousands. The qualification is the gate; what you do with the remaining down payment choices is left to the buyer.
The clearest signal that you should push for the next tier: when the incremental cash required is less than one third of the premium savings. At that ratio, you're effectively earning a triple-digit return on money you deploy once.
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