What is a good price-to-rent ratio?

Below 15: buying is clearly favoured. 15–20: neutral, depends on personal factors. Above 20: renting is financially smarter in most cases (common in expensive cities like NYC, SF, or London).

How long do I need to stay in a home for buying to make sense?

Typically 5–7 years to recover transaction costs and early mortgage interest. The break-even period is shorter when appreciation is high and longer in slow markets or high P/R ratio cities.

Does it make sense to buy in a high-cost city?

Often not from a pure financial standpoint — cities with P/R ratios above 25 (NYC, SF, London) heavily favour renting financially. Buying in these markets is often driven by stability, lifestyle, or forced savings goals rather than financial optimisation.

Is equity built through mortgage payments or appreciation?

Both. Each mortgage payment includes principal paydown (equity building) and interest (cost). Appreciation increases the market value of the equity. In early years, most of the mortgage payment is interest — principal build-up accelerates over time.

Formula Guide

How to Calculate Whether to Rent or Buy a Home

The rent-vs-buy decision is not just about monthly payments — it involves comparing total costs including mortgage interest, property taxes, maintenance, and the opportunity cost of a down payment against rent costs and the flexibility of renting. The break-even point is how many years you must stay in the home before buying becomes cheaper than renting. This calculation guides one of the most important financial decisions most people make.

Last updated: March 31, 2026

The Formula

Price-to-Rent Ratio = Home Price / (Annual Rent)
  < 15: buying favoured | 15–20: neutral | > 20: renting favoured

Annual Cost to Own ≈ Mortgage Payment×12 + Taxes + Insurance + Maintenance (1% of price) − Principal Paydown − Appreciation
Annual Cost to Rent = Annual Rent + Renter's Insurance

Break-Even Year = Year when cumulative cost to buy < cumulative cost to rent

Opportunity cost: the down payment invested in the market at a 7% average annual return should be included as a cost of buying — that money could be earning returns instead.

Variable Definitions

Symbol	Name	Description
P/R	Price-to-Rent Ratio	Home price divided by annual rent for a comparable property — a quick benchmark for whether buying or renting makes more financial sense
OC	Opportunity Cost	The return you forgo by using your down payment for a home purchase rather than investing it

Step-by-Step Example

Compare renting a $2,200/month apartment vs buying a comparable $450,000 home with a 20% down payment ($90,000) at a 6.8% 30-year mortgage rate.

Given

Home price:$450,000Down payment:$90,000 (20%)Mortgage rate:6.8% for 30 yearsMonthly rent:$2,200

Solution

1
Monthly mortgage payment (P&I): $360,000 at 6.8% / 30yr ≈ $2,355/month
2
Add property tax + insurance + maintenance: $2,355 + $375 + $125 + $375 = $3,230/month
3
Price-to-rent ratio: $450,000 / ($2,200 × 12) = $450,000 / $26,400 = 17
4
Annual cost to own vs rent gap: $3,230 − $2,200 = $1,030/month more to own initially
5
Estimate break-even (accounting for appreciation and principal build-up): ~6–8 years at 4% annual appreciation

P/R ratio of 17 is borderline. If staying 7+ years: buying builds equity. Under 5 years: renting is almost certainly cheaper.

Ready to calculate?

Use the free Rent vs Buy Calculator — instant results, no sign-up.

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Common Mistakes to Avoid

Comparing mortgage to rent directly — mortgage is only part of owning costs. Add taxes, insurance, HOA, and maintenance.

Ignoring the opportunity cost of the down payment — $90,000 invested at 7% annual return = $343,000 after 20 years.

Assuming home prices always appreciate — appreciation is location-dependent and not guaranteed.

Forgetting transaction costs — buying and selling each cost 2–5% of the home value in fees, which must be recovered before buying pays off.

Frequently Asked Questions

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