Why Duplex Pre-Approval Is Different

Getting pre-approved to buy a duplex as an owner-occupant requires a different conversation with your lender than a standard single-family home purchase. The key difference: your lender needs to understand you're buying an income property you'll also live in, and they need to know how to treat the rental income from the second unit in your qualification calculation. Not all lenders handle this the same way — which is why a mortgage broker is almost always better than going directly to a bank.

What Lenders Need to See

For a duplex pre-approval, prepare: 2 years of T4s or Notice of Assessment, most recent 3 months of pay stubs, 3 months of bank statements (all accounts), statement of all debts and monthly payments, proof of down payment source (3-month history of the funds), and for the rental income qualification — either a signed lease from existing tenants or a market rent estimate from your broker.

How Rental Income Is Calculated in Your Qualification

Two approaches lenders use. Gross-up method (A lenders): they take your rental income and add 50–80% of it to your qualifying income. If the second unit rents for $2,000/month, they might add $1,200–$1,600/month to your income for qualification. Rental offset method: they subtract the rental income from your monthly housing costs before applying the stress test. Both improve your qualification — but the gross-up method typically allows you to qualify for more.

The Stress Test: What You Actually Need to Qualify

In Canada, all insured mortgages are stress-tested at the greater of: your contract rate + 2%, or 5.25% (the current floor). For a $650,000 duplex with 10% down at 5.25%: stressed rate = 7.25%. Monthly payment at stressed rate: approximately $3,960. To qualify, your gross monthly income (including rental offset) must support this payment. At $90,000 personal income + $1,500 rental offset = effective qualifying income of approximately $105,000/year. This household qualifies.

Shopping Lenders: The 3 You Should Always Compare

1. Your existing bank — get a pre-approval, but don't commit. 2. A mortgage broker representing 30+ lenders — they'll find the best combination of rate, terms, and rental income treatment for your specific situation. 3. A credit union — often more flexible on rental income qualification and willing to lend to first-time investors who don't fit the big bank mould. Always compare all three before committing. The difference in terms can matter more than the difference in rate.