Where the money actually goes
Realtor commission is subject to GST, HST, or QST depending on your province, which is easy to forget when you're mentally splitting a 5% commission — the tax adds another meaningful chunk on top of the commission itself, and it's easy to underestimate your net proceeds if you forget to include it. If you're carrying a mortgage, check whether it has a prepayment penalty for paying it off before your term ends — that's a separate cost this calculator doesn't estimate, since it depends entirely on your specific lender and rate (see the mortgage penalty calculator to estimate that piece separately).
Commission structures vary more than people expect
The "5% commission" figure is a common benchmark, but actual structures vary by province and by agent. In BC and Alberta, it's common to see a graduated structure — a higher percentage (often around 7%) on the first $100,000 of the sale price, and a lower percentage on the remainder, which produces a different effective rate depending on the home's price. Commission is also always negotiable in Canada; there's no legally fixed rate, and what agents actually charge varies by market, service level, and how competitive the local real estate market is at the time.
Costs that are easy to forget
Beyond commission and its tax, sellers commonly underestimate a few other real costs: legal fees for the lawyer or notary handling the transaction, a mortgage discharge fee charged by your lender to formally release their claim on the property, and staging or minor repair costs to get the home market-ready. None of these are huge individually, but together they can add up to a few thousand dollars that's easy to overlook when mentally calculating "sale price minus mortgage balance" as your expected proceeds.
Selling and buying at the same time
If you're selling to buy again, the net proceeds from this calculator become the down payment (and cash cushion) for your next purchase — worth running both calculations together rather than in isolation, especially if the timing between your sale closing and your purchase closing is tight enough that you might need short-term bridge financing to cover the gap.
Buying your next place at the same time? Start with the mortgage payment calculator to see what your new payment would look like, or check HELOC options if you need to bridge the gap between closing dates.