How do lenders count rental income — and why does it decide how many doors I can hold?
The single biggest variable in your file isn’t the rate — it’s how a lender treats the rent, and the methods produce very different debt ratios on identical numbers. With an add-back, a percentage of gross rent is added to your qualifying income: insurers publish this approach, and CMHC allows up to 100% of gross rent on an owner-occupied 2-unit and up to 50% on 3-4 units1. With an offset, a share of rent is subtracted from the rental property’s own carrying costs, and only any shortfall lands in your TDS; the percentage varies by lender, and the more generous versions make a cash-flowing rental close to ratio-neutral.
The difference compounds. By door three or four, a borrower at a conservative lender can be ‘maxed out’ while the same borrower at a more generous one still has room. We map your file against all three before submitting, so you’re not declined by a methodology you never chose.

