Cash Dam vs. Smith Manoeuvre: What's the Difference?

"Cash dam" and "Smith Manoeuvre" get used almost interchangeably online, and it's easy to see why — both convert non-deductible interest into deductible interest, and both lean on the same rule in the Income Tax Act. But they solve different problems for different people.

What They Have in Common

Both strategies rely on Section 20(1)(c)'s traceability rule: borrowed money used for the purpose of earning income can have its interest deducted. Both require a readvanceable line of credit or HELOC. Both live or die on clean record-keeping.

Where They Split

• The Smith Manoeuvre re-borrows against your home equity to invest in income-producing securities — dividend stocks, ETFs, and similar.
• Cash damming uses a line of credit to pay existing, deductible rental property expenses — it doesn't require you to make a new investment at all.
• The Smith Manoeuvre is built for homeowners with equity and an appetite to invest. Cash damming is built for landlords who already have deductible expenses sitting on a rental property.
• You can run the Smith Manoeuvre without owning a rental property. You generally can't run cash damming without one.

Can You Do Both?

Yes — a homeowner who also owns a rental property can run both strategies at once, on separate lines of credit, as long as each one's paper trail stays clean and separate from the other. What you can't do is blur them together on a single account and expect CRA to sort it out for you.

Which One Is Right for You

If you own a rental property and want to make its existing costs work harder at tax time, start with cash damming. If you're a homeowner with equity looking to build an investment portfolio using your mortgage as leverage, that's the Smith Manoeuvre. Try the Mortgage-To-Millions™ Calculator to see how either one plays out on your numbers.