Buy vs rent in a high-rate market

How the gap opens up

Use a $600,000 home with 20% down (a $480,000 loan) and a 25-year amortization. At 4.5% the principal-and-interest payment is $2,657 a month. At 7.5% it is $3,511. Adding property tax, insurance, maintenance and utilities, the owner's first-month cash cost is $3,757 at 4.5% and $4,611 at 7.5%, compared with $2,325 for a renter paying $2,300 plus tenant insurance.

The monthly gap between owning and renting therefore grows from about $1,432 to about $2,286 in the first month. In the comparison, both households spend the same total budget, so the renter invests that gap.

The rest of the example is the usual illustrative base case: 3.5% yearly appreciation, $2,300 rent growing 3% a year, a 5.5% investment return, 2% inflation and a 10-year stay in Alberta. These are planning inputs, not current market data, and the 7.5% rate is a stress case rather than a statement of today's rates.

Does staying longer rescue the buyer?

In some cases a longer stay brings buying back into the lead. In a high-rate case it often does not, because every extra year carries heavy interest. On the base case at a 7.5% rate, the gap keeps widening with the stay length.

What could flip the result

Because the high-rate result is lopsided, it is worth asking which single change would make buying competitive. Each row below changes one thing from the 7.5% case (10-year stay, base case otherwise).

A few of these are in your control and some are not, which is why they are listed side by side.

Reading the table

Three lessons stand out. First, rent matters a great deal. At a 7.5% rate, a market where comparable rent is about $3,200 to $3,500 can make buying competitive, while one where rent is $2,300 cannot. The break-even rent for a 10-year stay at 7.5% is about $3,008, compared with about $2,067 at 4.5%.

Second, a later rate drop helps but does not fully repair the result by itself; a 4.5% renewal still leaves the buyer about $58,000 behind. Third, tweaks to the loan structure (more down, longer amortization) change the result only modestly compared with the rate itself. A longer amortization lowers the payment but adds interest.

Lowering the purchase price alone also does not flip the case if rent stays the same, because the comparison depends on the relationship between price and rent. See price-to-rent ratio explained.

The probability view

With the Monte Carlo option, the same 7.5% case shows buying finishing ahead in about 24% of 1,000 simulated paths, compared with about 61% at 4.5%. The simulated paths assume yearly volatility of 6 points for home values and 12 for investments, so the share is a statement about those assumptions.

Even so, 24% is not zero. If you are confident the home will do better than the assumed average, or that rates will fall quickly, you can enter those beliefs explicitly and see how the answer changes. The probability tool lets you do that.

When high rates still favour buying

High rates do not decide the question on their own. Some households buy for reasons that a net-worth comparison does not capture, such as stability, a long planned stay, a rental suite or the ability to modify the home. Others rent because flexibility is worth more than the potential equity.

If you are weighing a purchase at a high rate, a sensible checklist is:

• Find the break-even rent and compare it with what you would really pay to rent.
• Test a renewal rate above and below your starting rate (see mortgage renewal risk).
• Check what appreciation you would need and decide if it is a reasonable plan or a hope.
• Make sure you can carry the payment with a cash buffer, not just qualify for it.
• Compare with buy vs rent in a falling market to see the downside case.