How To Calculate Gross Rent Multiplier

The gross rent multiplier, or GRM, divides the property price by the gross annual rent. Gross means before any expenses, so vacancy, taxes, insurance and repairs are all ignored at this stage.

The result is read as years of rent. A GRM of 11.5741 means the price is about eleven and a half years of gross rent, and lower numbers generally mean better value.

There are two conventions in circulation. The annual GRM divides by twelve months of rent, while the monthly GRM divides by one month. They differ by a factor of twelve, so always check which one a listing quotes.

The monthly version is common in residential practice, where an agent might say a property trades at 140 times monthly rent. The annual version is more common in commercial work and is easier to compare with bond yields.

The gross yield is the reciprocal of the annual GRM. A GRM of 11.5741 gives a yield of 8.64 percent, and the two figures say the same thing in different units.

GRM ignores expenses entirely, which is both its strength and its weakness. It is fast and needs no bookkeeping, but a property with high taxes or a large repair bill can look excellent on GRM and still lose money.

Use it as a screen, not a decision. Filter a list of properties down to the three or four with the lowest GRM, then run a full cash flow analysis on each with real expense figures.

Comparisons only work within the same market. A GRM of 8 in one city and 15 in another reflect different tax regimes, vacancy rates and growth expectations, not a bargain in one place.

Rents must be market rents, not the current tenant's below-market rent. If the sitting tenant pays 200 below market, the GRM looks worse than the property really is.

Vacancy changes the picture. Gross rent assumes twelve months of payment, and a property with a one month void each year really earns eleven months, which is about 8 percent less than the gross figure suggests.

The cap rate is the more complete cousin. It divides net operating income by the price and accounts for expenses, so it usually shows a lower and more realistic return than the gross yield.

Target GRM is a quick affordability test. If you want a GRM of 10 and the price is 250000, the rent needs to be 2083.33 a month, and anything below that fails the screen.

A falling gross rent multiplier can signal a rising market rather than a better deal, because the denominator moves before rents catch up.

Short term rentals often show a very low multiplier, but the gross rent assumes near full occupancy that a long term let would never achieve.

Expenses excluded from the multiplier include management fees, repairs, void periods, insurance and ground rent, and together they can consume a third of the rent.

Because it ignores financing, the multiplier cannot tell you the return on your own cash, which is what actually matters to a leveraged investor.

Commercial multiples are usually quoted with the annual rent, so a unit trading at eight times gross rent has a gross yield of 12.5 percent.