How to Calculate Prorated Rent: Formula, Examples, and Move-In / Move-Out Scenarios
Prorated rent is what you pay when you move in or out partway through a month. This guide shows the two main formulas (daily rate and banker's method), walks through move-in and move-out examples, and flags the edge cases landlords and tenants fight about.
Prorated rent is the partial-month amount you owe when you move in or out partway through a month. Take the monthly rent, divide by a divisor (the actual days in the month or a flat thirty-day month), then multiply by the days you actually occupy the place:
prorated rent = monthly rent ÷ divisor × days occupied.
Skip the arithmetic entirely with our prorated rent calculator.
A move-in partway through the month is the most common case. Pay for the days you live there, then full rent on the first of the next month.
That covers the move-in day through the end of the month. The rest of this guide is about which divisor to use, how to handle short and long months, and what to do when a landlord insists on a different method.
The two prorated rent formulas
Both methods are defensible. Leases usually specify which one applies, but many do not. The first uses the real length of the calendar month, so the divisor changes with each month. It is the most literal reading of "prorate" pay for the exact fraction of the month you were there.
The banker's method flattens every month to a fixed length. Tenants moving in during February prefer it because the daily rate comes out lower. Landlords often prefer the actual-month method for the same reason.
A third method spreads rent across the whole year. It is the fairest over twelve months but uncommon in residential leases, closer to what commercial property uses.
Move-in prorated rent, worked
One move-in date can produce three different answers. Take a mid-month move-in to a long calendar month, counting the move-in day through the end of the month as occupied. Each method lands somewhere different, which is exactly why the lease should name the method.
Short months swing the result the other way. Move in mid-February in a non-leap year, counting from the move-in day to the end of the month, and the flat-month divisor now favors the tenant.
Move-out prorated rent, worked
Move-outs are the mirror image: you pay for days lived, not days remaining. In a thirty-day month the two common methods agree, because the divisor matches either way.
A longer month splits them apart again. Moving out partway through a thirty-one-day month means the first of the month through the move-out day count as occupied, and the actual-month divisor produces a lower bill.
Does the move-in day count?
By convention, the tenant pays for the day they move in, not the day they move out. So a move-in on a given date means that date is included, running through the end of the month. Some landlords use the opposite convention. The only reliable way to avoid a dispute is for the lease to state which days are included.
Daily rent, weekly rent, and rent per day
Quoted daily and weekly rates are almost always derived from the monthly figure. Short-term corporate rentals and some UK lets quote a weekly figure directly instead.
For the UK-specific conventions, see our pro rata rent UK guide.
Edge cases landlords and tenants fight about
A mid-month rate change is prorated in two pieces, not averaged. Bill the old rate for the days before the change and the new rate for the days after.
A lease that starts and ends mid-month gets prorated at both ends. The middle months bill at full rent.
February distorts the actual-month method. The same monthly rent produces a higher daily rate in February than in a longer month, so a February move-in costs more per day than the same date in a thirty-one-day month.
Leap years add a day. The extra February day counts as a day lived, and the actual-month divisor becomes the leap-year length.
Security deposits stay separate from prorated rent. Never subtract a deposit from prorated rent at move-in without written agreement.
What to put in a lease
Three sentences prevent most disputes. Name the divisor, fix the day convention, and state the dollar amount before move-in so nobody is computing from scratch later.
Common mistakes
Dividing by a flat month when the lease says otherwise. The lease wins. Read it before computing.
Forgetting to count the first or last day. Verify which days are included first.
Treating the calendar date as the day count. A move-in date partway through the month is fewer occupied days than the date number suggests, because you count from the move-in day to the end of the month.
Prorating against the wrong rent figure. When rent is scheduled to rise on the first, use the rate that applies on each day being counted.
Pick one method, write it into the lease, and state the dollar amount before move-in. For a zero-math answer, drop your dates and rent into our prorated rent calculator, and for UK-specific conventions see our pro rata rent UK guide.
Common questions
Divide the monthly rent by a divisor, then multiply by the days you occupy the unit: prorated rent = monthly rent ÷ divisor × days occupied. The divisor is either the actual number of days in that month or a flat thirty-day month, depending on what the lease specifies.
Follow the lease. If it is silent, the actual-month method is the more literal reading, while the flat-month method is simpler and consistent across the year. The two only diverge in months that are not exactly thirty days long.
By default, yes. The standard convention charges for the move-in day and not the move-out day. Either convention is valid, so the lease should state which days are counted to avoid a dispute.
The extra February day counts as a day occupied. If you use the actual-month method, the divisor becomes the leap-year length of February rather than the usual non-leap-year count.
Split the month into two periods. Charge the old rate for the days before the change and the new rate for the days after, then add them. Do not average the two rates.
