Prorated Rent: 30 or 31 Days?
Why calculators give different answers, and which one applies to you.
The Short Answer
Prorated rent is a daily rate times the days you live there that month. Calculators disagree because there are three common daily rates: rent ÷ the days in that month, rent ÷ 30, and rent × 12 ÷ 365.
For $1,500 rent and a move-in on February 15, 2025, they give $750.00, $700.00 and $690.41. All three are correct arithmetic. Your lease decides which one applies.
Compare all three for your date →The Worked Example
Rent is $1,500. You move in on February 15, 2025, which is not a leap year, so February has 28 days. Counting the move-in day, you pay for February 15 to 28: 14 days.
| Method | Formula | Rent due |
|---|---|---|
| Actual days | 1,500 ÷ 28 × 14 | $750.00 |
| 30-day month | 1,500 ÷ 30 × 14 | $700.00 |
| Yearly rate | 1,500 × 12 ÷ 365 × 14 | $690.41 |
That's a $59.59 gap for the same two weeks. February makes it bigger than usual, because dividing by 28 makes each February day the most expensive day of the year.
How to Work Out Yours
- Find the method in your lease. Look for “prorated”, “daily rate” or a sentence about the first or last month.
- Count the days you are paying for. Moving in on day D of a month with N days, that is N − D + 1 if the move-in day counts. Moving out on day D, it is D if the move-out day counts.
- Work out the daily rate with your lease's method.
- Multiply the daily rate by the days, and round to the cent at the end.
- If the lease doesn't say, ask the landlord which method they used and to show the numbers. Comparing them with the prorated rent calculator shows straight away which method matches.
Things That Trip People Up
- Counting the move-in day. Leave it out and February 15 becomes 13 days: $696.43, $650.00 or $641.10. It's the same off-by-one problem as counting days between two dates.
- Leap years. Moving in on February 15, 2024 means 15 days out of 29: $775.86, $750.00 or $739.73.
- 31-day months flip the order. Moving in on March 15, 2025 (17 days out of 31), the 30-day method is the most expensive: $850.00, against $822.58 by actual days and $838.36 by the yearly rate.
- Rounding the daily rate first. 1,500 ÷ 28 is 53.5714…. Rounded to $53.57 before multiplying, 14 days come to $749.98 instead of $750.00. A few cents' difference often comes from this.
- A whole month is not prorated. Moving in on the 1st with the move-in day counted means you owe the full month by every method.
Leases and Local Rules
Which method applies, and whether a partial month is prorated at all, is set by your lease. Some places also have rules about rent and when it is due. This guide is arithmetic, not legal advice. Check your lease, and your local tenant or housing office if something looks wrong.
When you move out, the lease may also set notice periods that matter more than the daily rate. Read that section before working out a final partial month.
Frequently Asked Questions
Is prorated rent based on 30 days?
Sometimes. Some landlords divide the monthly rent by 30 every month, some divide by the actual days in that month (28 to 31), and some use a yearly daily rate of rent times 12 divided by 365. Your lease decides, so look for the word prorated or daily rate in it.
How do I calculate prorated rent for a move-in?
Count the days from your move-in date to the end of the month, including the move-in day if your lease charges it. Multiply that by the daily rate. For 1,500 rent and a move-in on February 15, 2025, that is 14 days, which gives 750.00, 700.00 or 690.41 depending on the method.
Why is my prorated rent so high?
Usually because of February or the method. In February the actual-days method divides by 28, so each day costs more than in any other month. In a 31-day month the 30-day method costs more, because it charges 1/30 of the rent per day. Check the day count too: counting the move-in day adds a full day.
Does prorated rent include the move-in day?
Usually, because you have the keys that day, but it is a convention set by the lease. Leaving it out removes one day. For the February 15 example, it is 13 days instead of 14, which gives 696.43 instead of 750.00 by the actual-days method.
How is prorated rent calculated in February of a leap year?
With the actual-days method you divide by 29 instead of 28. Moving in on February 15, 2024 with 1,500 rent means 15 days at 1,500 divided by 29, which is 775.86. The 30-day method gives 750.00 and the yearly method 739.73.
Which method is correct?
All three are correct arithmetic. None is wrong in general; the right one is the one your lease names. If the lease is silent, ask the landlord which method they use and to show the calculation. Some places have local rules on rent, so check those too.