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Moving in or out mid-month? Enter the rent and the date to get the partial month amount, with the daily rate and the formula behind it.
Prorated rent divides the monthly rent into a daily rate, then charges only the days the tenant holds the unit. The standard formula uses the actual days in that month: Daily Rate = Monthly Rent ÷ Days in Month, then Prorated Rent = Daily Rate × Days Occupied. On a $1,900 unit with a September 18 move-in: $1,900 ÷ 30 = $63.33 a day, times 13 days of occupancy, which comes to $823.33.
Two other conventions show up in real leases. The banker's month method divides by a flat 30 regardless of the calendar, which keeps the daily rate constant all year. The 365-day method multiplies the rent by 12, divides by 365, and charges that daily rate per day. All three are legitimate, and the lease language decides which one applies. This calculator shows all three so the difference is visible before it becomes a dispute.
The three methods agree in a 30-day month and diverge everywhere else. February is the extreme case: dividing by 28 produces the highest daily rate of the year, while the 365-day method barely notices the short month.
In a 31-day month, the 30-day and 365-day methods can price the partial month above the full month's rent, because their daily rates ignore the calendar. No lease bills more than a month, so this calculator caps both at one month's rent.
Move-out proration counts the day the tenant leaves. A lease that runs through the 10th charges 10 days, because the tenant holds the unit that day.
No federal rule requires a landlord to prorate at all. The lease and state law control both whether proration happens and which method applies, so the calculation that governs is the one written into the lease.
Divide the monthly rent by the number of days in that month to get a daily rate, then multiply by the days occupied. A move-in on September 18 pays for 13 days: the 18th through the 30th. At $1,900 a month, that is $63.33 a day and $823.33 for the partial month.
Actual days in the month is the most common because it matches the calendar. Large property managers sometimes prefer the flat 30-day month because the daily rate never changes. Whichever method appears in the lease is the one that governs.
Under most leases, yes. The tenant holds the unit through the move-out date, so that day counts as occupancy. A lease ending on the 10th prorates 10 days, not 9.
The actual-days method divides by 28, which produces the highest daily rate of the year. The 30-day and 365-day methods ignore the short month, so the gap between methods peaks in February. The shorter the month, the more the method choice matters.
No general law requires it. Proration is a lease term, not a right, and a landlord can require a full month for a mid-month move-in if the lease says so. State and local rules vary, so a dispute over proration is a question for the lease first and a local attorney second.