Does a non-resident seller pay Canadian tax the same way as a Canadian resident seller?

Not entirely. A non-resident selling shares of a Canadian corporation, or certain other Canadian business property, is still generally subject to Canadian tax on the resulting gain, so the basic concept of paying tax on the sale isn't avoided just by living outside Canada. But the process and some of the entitlements differ meaningfully from a resident seller's position.

Most significantly, the Lifetime Capital Gains Exemption is generally tied to Canadian residency requirements that a non-resident typically cannot meet, so a non-resident seller usually cannot shelter their gain the way a Canadian-resident individual with qualifying shares could. Non-resident sellers are also subject to a separate compliance process: unless they obtain clearance from the CRA confirming their Canadian tax obligations are addressed, the buyer is required to withhold part of the purchase price and remit it to the CRA, which affects both the timing of when the seller actually receives full payment and the paperwork involved in closing the deal.

A non-resident seller should expect a more involved compliance process, less access to Canadian personal exemptions, and a real need for Canadian tax advice, ideally arranged well before a closing date is set.