Rent calculators
Prorated rent, pro rata, and why your tenant's figure differs from yours.
A part month has three defensible answers, not one. Put the rent and the date in, and see all three with the arithmetic under each, so you can tell which one your lease is actually asking for.
The month, and the part they hold
17 of 31 days
Actual days in the month
Rent divided by the real length of this month
€823
€48 a day over 17 days, dividing by 31
Thirty day month
Rent divided by 30, whatever the month
€850
€50 a day over 17 days, dividing by 30
Yearly average day
A year of rent divided by 365
€838
€49 a day over 17 days, dividing by 30.42
Those three answers differ by €27 on this one month. Whichever your lease names is the one that governs.
Nothing is stored and nothing is sent. The figures stay in this browser.
Prorated rent meaning
Prorated rent meaning: the part of a month somebody actually lived there.
A tenancy rarely starts on the first. Proration, or pro rata rent, is how a full monthly rent is cut down to the days the tenant holds: turn the month into a daily rate and charge for the days they have. The whole difficulty is which number you divide by.
What it is
A daily rate, multiplied by days held
Both ends count. A tenant who takes the keys on the 15th sleeps there on the 15th, so a move-in on the 15th of a 31 day month is 17 days, not 16.
When it applies
The first month, the last month, and nothing between
Every month in the middle is a full month at the full rent. Proration is a beginning and an end, which is why it is easy to get wrong: you only do it twice per tenancy.
Who it is for
Both sides, and they are reading different pages
A tenant works it out on a calculator they found. You work it out on yours. If the two used different divisors the figures will not match, and neither of you is wrong.
Why there are three answers
Same rent, same date, three day rates.
The monthly rent is fixed. What is not fixed is how many days you divide it by, and every convention below is in live use somewhere. The gap between them is small on one month and permanent across a portfolio.
What one day costs, by method
On €1.500 a month
Actual days in the month
€48 a day
Thirty day month
€50 a day
Yearly average day
€49 a day
The thirty day rate is the highest of the three in a 31 day month and the lowest in February. It is the commonest convention in US leases and in almost all commercial ones, which is why a residential tenant and a landlord reading different habits disagree so reliably.
February costs more per day, and nobody warns you
Divide by the real length of the month and a short month makes each day dearer, because the same rent is spread over fewer of them. The tenant moving in on the 10th of February pays a higher daily rate than the one who moved in on the 10th of January, for the same flat.
- A 31 day month
- €48 a day
- A 28 day month
- €54 a day
A gap of €5 a day on the same rent, purely because the months are different lengths.
What the disagreement costs
It is never about the money. It is about the first bill being wrong.
The sums here are small. What they buy you is an argument in the first week of a tenancy, with somebody you now have to deal with for a year, about whether you can be trusted with arithmetic.
An argument on day one
The first invoice is the first thing you ever send a new tenant. A figure they cannot reproduce is the worst possible opening, and it is remembered long after the amount is forgotten.
A lease that settles nothing
Most leases give the rent and the start date and say nothing about how a part month is worked out. That silence is what makes both figures defensible, and it is why the argument has no natural end.
The same mistake, once per tenancy
You prorate twice per tenancy and then not again for a year, so nothing ever becomes a habit. Across a portfolio it is the calculation most often done from memory and most often done differently each time.
How to settle it for good
Name the method in the lease and the argument cannot start.
This is not a legal problem and it does not need a lawyer. It needs one sentence, written once, that says which number you divide by. After that the calculation is arithmetic and both sides get the same answer.
- Step 1
Pick one and keep it
Actual days in the month is the easiest to defend, because it is the only method where a full month of occupation costs exactly one month of rent.
- Step 2
Put it in the lease
One line, in the rent clause, naming the divisor and saying that both the first and last day count. The clause below is that line.
- Step 3
Show the working on the invoice
Daily rate, days, total. A tenant who can reproduce your figure does not write to you about it, and that is the whole return on the sentence.
- Step 4
Use the same one next time
The cost of this is not the first calculation, it is the fourth one done differently. Whatever you choose, apply it to every unit and every move-out as well as every move-in.
The sentence that ends it
A plain clause naming the divisor and the inclusive count. Adapt the wording to your own lease and have it checked where local law sets a rule, because a few jurisdictions do prescribe a method.
Where this tenancy begins or ends part way through a calendar month, the rent for that month is the monthly rent divided by the number of days in that calendar month, multiplied by the number of days of the tenancy in that month, counting both the first and the last day.
This is a drafting suggestion, not legal advice. Some jurisdictions prescribe a proration method, and where they do, the law overrides whatever the lease says.
The questions that follow.
What does prorated rent mean?
Prorated rent is the part of a month a tenant actually pays for when they move in or out part way through it. Instead of a full month, the rent is divided into a daily rate and charged for the days they hold the property, both the first and last day included.
How do you calculate prorated rent?
Divide the monthly rent by a number of days to get a daily rate, then multiply by the days the tenant holds. The divisor is the part that varies: the actual number of days in that month, a flat 30, or 365 divided by 12. Round once, at the end, rather than rounding the daily rate first.
Which proration method is correct?
None of them is correct in itself. The one your lease names is the one that governs. Where the lease is silent, the actual days in the month is the most common default and the easiest to defend, because it is the only one where a full month of occupation costs exactly one month of rent.
Is the move-in day charged?
Normally yes. A tenant who takes the keys on the 15th sleeps there on the 15th, so the count runs from that day to the end of the month inclusive. A move-out is counted the same way, from the first of the month to the last day of occupation.
Can prorated rent be more than a month of rent?
On the 30 day method, yes. A full 31 day month charged at a thirtieth of the rent per day comes to slightly more than the monthly rent. That is what the convention says, and it is why some leases add a line capping a part month at one full month.
Does proration affect the deposit?
No. The deposit is set by the lease and by the cap in your jurisdiction, and it is not scaled to a part month. Proration applies to the rent for that month only.
Working it out was never the hard part.
You can do this sum in a minute. What costs you the afternoon is finding the lease, remembering which method you used in March, and explaining it to a tenant eleven months later who has the figure in front of them and you do not.
- The lease is the record, not your memoryRent, start date, end date and terms sit on the tenancy itself, so the figure you quoted in March is still there in February when somebody asks about it.
- One number, and the tenant sees the same oneThe invoice, the ledger and the answer Dardaris gives a tenant all come off the same record. There is no second copy to drift.
- And a trail of what was doneEvery figure that goes out carries who raised it and when. An amount you cannot explain eleven months later is the thing this is built to stop.
The number is the easy part.
Dardaris keeps the lease, raises the invoice, matches the payment and writes down what it did. Bring one building and watch a month before you decide anything.
14 days before the first charge · Nothing is switched on until you say so