Prorated Rent Calculator
Calculate prorated rent for a partial move-in or move-out month. Enter monthly rent, days in the month and days occupied to get the exact rent you owe.
Updated 2026-06-14 · Free · No sign-up · Runs privately in your browser
Show the formula & steps
How the Prorated Rent Calculator Works
When you move in or out partway through a month, you should only pay for the days you actually occupy the home. Proration splits a full month’s rent down to a fair, per-day amount. This calculator does that in one step: enter your monthly rent, the number of days in the month, and the days you occupy the unit, and it returns the exact rent due.
The result updates instantly, and the steps panel shows the daily rate and the arithmetic so you can verify it against your landlord’s invoice.
The Formula
Proration is built on a simple daily rate:
Daily rent = monthly rent ÷ days in month Prorated rent = daily rent × days occupied
The only judgment call is which value to use for “days in month.” The three common conventions are:
- Actual days — divide by the real number of days in that month (28, 29, 30 or 31). This is the method most tenant-landlord guides and courts treat as fairest.
- Flat 30-day — always divide by 30, regardless of the real calendar.
- Banker’s / annualized — use the daily rate of (annual rent ÷ 365), i.e. monthly rent × 12 ÷ 365.
Set the days in month field to match whatever your lease specifies.
Worked Example
Say your rent is $1,500/month, you move in on the 19th of a 30-day month, and you count the move-in day through the 30th (12 days occupied):
- Daily rent = $1,500 ÷ 30 = $50.00 per day
- Prorated rent = $50.00 × 12 = $600.00
- You save = $1,500 − $600 = $900.00 versus a full month
So your first rent payment for that partial month is $600, not the full $1,500.
Counting Days Occupied Correctly
The most common mistake is miscounting the occupied days. Count inclusively from the move-in date to the end of the month.
| Scenario | Days in month | Days occupied | How to count |
|---|---|---|---|
| Move in on the 1st | 30 | 30 | Full month — no proration |
| Move in on the 19th | 30 | 12 | Days 19–30 inclusive |
| Move in on the 15th | 31 | 17 | Days 15–31 inclusive |
| Move out on the 10th | 31 | 10 | Days 1–10 inclusive |
| Move in on the 16th | 28 (Feb) | 13 | Days 16–28 inclusive |
For a move-out, count from the 1st of the month through your last day in the unit. Always confirm the method and day-counting with your lease so your figure matches the landlord’s, and keep the daily-rate breakdown handy in case you need to dispute a charge.
Frequently asked questions
How do you calculate prorated rent?+
Divide the monthly rent by the number of days in the month to get the daily rent, then multiply by the number of days you occupy the unit. For $1,500 rent in a 30-day month occupying 12 days: $1,500 ÷ 30 = $50/day, then $50 × 12 = $600 prorated rent.
Should I use 30 days or the actual days in the month to prorate rent?+
Both methods are common. The actual-days method divides by the real days in that month (28–31), which most courts and leases consider the fairest. Some landlords use a flat 30-day or a banker's 365 ÷ 12 method. Check your lease, and use the days-in-month field to match whichever your landlord applies.
If I move in on the 19th of a 30-day month, how much rent do I owe?+
You occupy the unit from the 19th through the 30th, which is 12 days. Multiply the daily rent (monthly rent ÷ 30) by 12. For $1,500 rent that is $50 × 12 = $600 for the partial first month.
Is prorated rent legal and required?+
Proration is standard practice and many leases require it, but specific rules vary by state and lease terms. Landlords generally prorate the first or last month when a tenant does not occupy the full month, though it is the lease, not a universal law, that governs the exact method.
Do I count the move-in day when proration?+
Yes. The move-in day is typically counted as an occupied day. Count every day from your move-in date through the last day of the month (inclusive) and enter that total as days occupied.