Prorated Rent Calculator
Move in on any day but the first and the first payment is a partial month: prorated rent. There are two legitimate ways to compute it, and they give different answers. The actual-days method divides the monthly rent by that month's real day count; the banker's-month method divides by a flat 30. On a $1,550 rent with a mid-month move-in the two can differ by several dollars, which is a small number that generates an outsized share of landlord-tenant friction. This calculator shows both, so whichever the lease names, both sides can see the arithmetic.
- Days occupied (incl. move-in day)
- 15 of 31
- Prorated rent (actual days in month)
- $750.00
- Daily rate (actual method)
- $50.00
- Prorated rent (30-day 'banker's month')
- $775.00
Most leases and most states' practice use the actual-days method. The 30-day method is a convention some landlords prefer; whichever applies should be the one written in the lease.
What to Know
- The move-in day itself counts as an occupied day: moving in on the 17th of a 31-day month means paying for 15 days, not 14.
- The actual-days method is the default in most states' practice and most leases; the 30-day banker's month is a convention, not a law, and should only be used when the lease says so.
- In February the two methods diverge most: a 28-day month makes each actual day worth more than a thirtieth of the rent, so the actual method charges more per day in February and less in 31-day months.
- A few states (California among them, via case-law convention) expect proration when the landlord chooses the move-in date; nowhere is a full month's rent for a partial month good practice.
- Prorated move-out works the same way in reverse: days occupied up to and including the handover day, over the days in that month.
Frequently Asked Questions
Which proration method should we use?
Whichever the lease specifies. If the lease is silent, actual days in the month is the widely accepted default and the harder one to dispute, because it maps each day to its real share of the month.
Does the move-in day count as a rent day?
Yes. If you take possession on the 17th, the 17th is your first paid day. Counting from the 18th shortchanges the landlord by one day and is the most common off-by-one in proration disputes.
Should prorated rent be on the receipt?
Yes: state the period it covers ('Aug 17 to Aug 31'), the method, and the amount. A rent receipt that names the period is what settles the question months later; our rent receipt generator has a field for exactly this.
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