Prorated Rent Calculator
Enter the monthly rent and move-in date to get the exact partial-month rent — daily rate, days occupied, and the formula behind the number.
Divides rent by the real number of days in the move-in month (28–31).
Your prorated rent appears here
Enter the monthly rent and a move-in date to see the days occupied, daily rate, and exact amount due.
How prorated rent works
Prorated rent is a partial month's rent charged when a tenant moves in (or out) on any day other than the first of the month. Instead of collecting a full month for a unit the tenant only occupied for part of it, you charge for exactly the days they lived there. It keeps the first payment fair, gets the tenancy off to a good start, and lines every following payment up with the 1st of the month.
Method 1: actual days in the month
Divide the monthly rent by the real number of days in the move-in month — 28, 29, 30, or 31 — then multiply by the days the tenant occupies, counting the move-in day itself. A $1,500 unit in July (31 days) has a daily rate of $48.39; a July 20 move-in covers 12 days, so the prorated rent is $580.68. This method mirrors the calendar exactly, which most tenants find intuitive, but the daily rate changes from month to month.
Method 2: the 30-day "banker's month"
Divide the rent by a flat 30 regardless of the calendar. That same $1,500 unit always has a $50.00 daily rate — in February, July, or any other month. It is simpler to quote and keeps the rate consistent year-round, though it slightly overcharges in 31-day months and undercharges in February relative to the calendar.
Which method should you use?
Either is fine in most of the US — what matters is that your lease names the method and you apply it consistently. If you advertise and operate in a market where tenants compare listings closely, actual-days feels the most transparent. If you manage several units and want one daily rate you can quote from memory, the banker's month is hard to beat. Once the prorated first payment clears, tools like online rent collection keep every full month after it automatic.
Don't forget mid-month move-outs
Proration works in reverse at the end of a tenancy: a tenant leaving on the 10th owes 10 days, not the full month. Use the same method your lease specifies for move-ins, and note that for a move-out you count from the 1st through the departure day rather than to the end of the month. Keeping a clean record of each tenancy — dates, amounts, and the method used — avoids disputes over the final balance and the security deposit.
Educational content, not legal or tax advice — lease and proration rules vary by state and city, so consult a professional for your situation.
Frequently asked questions
Quick answers about prorating rent for partial months.
How do I calculate prorated rent for a mid-month move-in?
Divide the monthly rent by the number of days in the billing month to get a daily rate, then multiply by the number of days the tenant occupies the unit, counting the move-in day itself. For example, $1,500 rent in a 31-day month is $48.39 per day; a move-in on the 20th means 12 days of occupancy, or $580.68. The calculator above does this math for you with either proration method.
Should I use the actual-days method or the 30-day month?
Both are widely used. The actual-days method divides rent by the real length of the move-in month (28-31 days), so the daily rate shifts slightly month to month. The 30-day banker's month uses a flat 30-day divisor, which keeps the daily rate identical year-round and is simpler to explain. Whichever you pick, write it into your lease and apply it consistently to move-ins and move-outs.
Is prorating rent required by law?
In most US states, proration for a mid-month move-in is a matter of agreement between landlord and tenant rather than a statutory requirement, though some states and cities do regulate it in specific situations. Put the proration method in the lease so there is no ambiguity. This page is educational, not legal advice — check your state and local rules or consult an attorney for your situation.