Find the rent owed for a partial month — moving in or out partway through a billing period.
How it works
Prorated rent is monthly rent × (days occupied ÷ days in month). $1,500 monthly rent for 15 of 30 days comes to $750.
What this does not include
This uses the actual number of days in the specific calendar month. Some leases instead use a fixed 30-day month for every proration calculation regardless of the actual month length — check your lease’s specific method, since the two can give slightly different results.
How to use this calculator
- Enter the full monthly rent.
- Enter the number of days actually occupied.
- Enter the total days in that calendar month.
A worked example
$1,500 monthly rent, occupying 15 of 30 days: prorated rent = 1,500 × (15/30) = $750.
$2,000 monthly rent, occupying 10 of 31 days: prorated rent = $645.1613.
What the variables mean
| Variable | Meaning |
|---|---|
| Monthly rent | Full month’s rent amount |
| Days occupied | How many days the tenant actually occupies the unit that month |
| Days in month | Total days in that specific calendar month |
Edge cases worth knowing
The days-in-month figure changes the daily rate. The same monthly rent produces a slightly different daily rate in a 30-day versus 31-day month, which is why this calculator asks for the actual month length rather than assuming a fixed 30 days.
A days-in-month of zero makes the calculation impossible, so the calculator declines to show a result for that input.
Why do landlords use actual days in month instead of a flat 30?
It’s more precise — a day’s rent in February is worth slightly more than a day’s rent in a 31-day month under this method, since the same monthly rent is being divided across fewer days.
Does “days occupied” include the move-in day itself?
Convention varies by lease — most commonly the move-in day counts as an occupied day; check your specific lease agreement for how it defines the count.
How would I prorate a move-out instead of a move-in?
The same formula applies — just use the number of days occupied before moving out instead of days occupied after moving in.
