This tool is a math helper, not legal or accounting advice. Your lease should state which proration method applies; apply the same method to every tenant. The security deposit is not prorated. City or county rules can occasionally differ.
Stop doing partial-month math by hand
Keep the date range, proration method and itemized move-in total with your rental records. This public calculator does not create an invoice or post a ledger entry. Explore Rentari's rental workflows and current plans and service fees before choosing your next step.
The questions landlords and renters actually ask about prorated rent.
How is prorated rent calculated?
Divide the monthly rent by the number of days to get a daily rate, then multiply by the number of days the tenant is responsible for. The daily rate can be based on the actual number of days in that month, a flat 30-day month, or the monthly rent times 12 divided by 365. The method should be stated in the lease.
Which proration method should I use?
Actual days in the month is commonly used for residential rent because it follows the calendar. A flat 30-day method is another lease convention. Compared with actual-day calculation, it yields a higher daily rate in 31-day months and a lower daily rate in shorter months. Follow the lease and apply its method consistently.
When is the 365-day-year method used?
This method converts monthly rent to annual rent (monthly rent multiplied by 12), divides by 365, then multiplies by the days charged. Buyers and sellers sometimes use it to allocate rent when a rental-property sale closes mid-month. Check the sale documents and applicable lease terms for the agreed method. This calculator uses a 365-day divisor, including in leap years.
Is the move-in day counted?
Usually yes. Rent is normally charged for the move-in day through the last day of the month, counted inclusively. This calculator counts the move-in day and the move-out day.
Do I prorate the security deposit too?
No. The security deposit is a fixed amount set in the lease and is not prorated. Only rent is prorated for a partial month. Check your state's deposit cap with our
security deposit calculator.
Can I prorate a move-out?
The move-out calculator counts from the first of the month through the date entered. Check the lease, any agreed ending terms and applicable rules before treating that result as the amount due. Moving out early does not by itself establish a rent reduction.
How should I record the prorated amount?
Write down the monthly rent, method, dates included and rounded rent result. With $1,200 monthly rent and an April 16 move-in, the actual-days method counts 15 of April's 30 days: $40 per day, or $600 rent. An entered $1,500 deposit and $100 of other permitted costs would make the illustrative move-in total $2,200; keep those items separate from rent. Confirm the agreement and applicable limits before adding a charge. Save the agreed amount and payment schedule, then reconcile actual payments separately.
