Prorated rent calculator

How do you calculate prorated rent?

Work out a daily rate, then multiply it by the number of days the tenant has the unit that month. For a move-in, count from the move-in day to the last day of the month. For a move-out, count from the 1st to the move-out day. The three methods differ only in how they get the daily rate:

• Days in that month. Divide the rent by 28, 29, 30 or 31, depending on the month. The daily rate changes from month to month, but a full month always adds up to exactly one month's rent.
• 365-day year. Multiply the rent by 12 and divide by 365. Every day costs the same all year, so a day in February costs the same as a day in July.
• 30-day month. Divide the rent by 30, whatever the month. It's the simplest to work out by hand, and the one that strays furthest from the calendar in 31-day months and in February.

Which method gives the lowest prorated rent?

In a 31-day month the days-in-month method gives the lowest figure and the 30-day method the highest, because it spreads the rent over fewer days than the month has. In every other month the 365-day year comes out lowest, since it treats each month as about 30.4 days long. In February the days-in-month method is the most expensive, and in a 30-day month it matches the 30-day method. In September the three answers for our $1,500 example are $7.53 apart; in October, with the same move-in day (12 days left in a 31-day month), they are $580.65, $591.78 and $600.

Which method should a landlord use?

The one your lease names. If the lease is silent, pick one, say which in writing before the tenant moves in, and use it every time. Local rules can also apply, so check them if you're unsure. Rent collection apps can bill the prorated amount for you; Zillow Rental Manager, for example, lets landlords request prorated rent as a one-time payment¹.