Nobody Should Pay a Full Month for Half a Month of Keys
Most leases start on the 1st — but real life rarely does. You sign on the 12th, get the keys on the 18th, or move out on the 9th, and suddenly someone has to answer: how much of this month’s rent is actually fair? That fair share is called prorated rent, and getting it wrong either overcharges the tenant or shortchanges the landlord.
This free prorated rent calculator does the whole job for you: enter the monthly rent, pick the month and year, add your first and last occupied days, and it figures out the exact days in the month (including leap years), the daily rate, and the precise amount owed — with a plain-English breakdown you can show your landlord or tenant.
Monthly rent · move-in · move-out · partial month
Your prorated rent
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How to Use This Calculator
- Enter your monthly rent — the full agreed rent for a complete month (e.g., 1500).
- Select the month and year — the partial month being calculated. Leap years are handled automatically.
- Enter your first occupied day — the day of the month you move in (1 if you were there the whole month).
- Enter your last occupied day — the day you move out (the month’s last day if you stayed to the end).
- Click “Calculate Prorated Rent” — you get the amount owed, the daily rate, the days counted, and a step-by-step explanation.
What Is Prorated Rent?
Prorated rent is a partial month’s rent, scaled down to match the days you actually occupy the property. Instead of charging a full month when you only live there for part of it, you pay a daily rate — your monthly rent divided by the number of days in that specific month — multiplied by the number of days you lived there.
It comes up most often with mid-month move-ins and move-outs, short-term stays, and lease breaks. The principle behind it is simple: rent pays for shelter on a given day, so a day you don’t live there shouldn’t cost you.
The Prorated Rent Formula
Prorated rent = Daily rate × Days occupied
Days occupied includes both the move-in and move-out days.
Worked example
Say your rent is $1,350, you move in on September 11 (2026), and you stay through September 30:
- Days in month: September 2026 has 30 days
- Daily rate: $1,350 ÷ 30 = $45.00 per day
- Days occupied: the 11th through the 30th = 20 days
- Prorated rent: $45.00 × 20 = $900.00
So instead of the full $1,350, you owe $900.00 for those 20 days — and the calculator above will show you the same math for any month, automatically adjusting for February in leap years.
Three Ways to Count the Days
Three daily-rate methods are in common use, and they give different numbers. On a $2,400 rent with a move-in on October 18 (14 occupied days):
| Method | Daily rate | 14 days owed |
|---|---|---|
| Actual days in the month (÷ 31) | $77.42 | $1,083.87 |
| Annual method (rent × 12 ÷ 365) | $78.90 | $1,104.66 |
| Flat 30-day month (÷ 30) | $80.00 | $1,120.00 |
The actual-days method — the one this calculator uses — matches the real calendar: February yields the highest daily rate, 31-day months the lowest. The flat 30-day method is simpler to bookkeep but overcharges in long months; the annual method lands in between. Round only the final total, never the daily rate.
When Prorated Rent Applies
- Mid-month move-in — the most common case: you get the keys on the 15th, you pay from the 15th.
- Early move-out — your lease ends on the 8th of the final month instead of the 31st.
- Short-term or temporary stays — anything shorter than a full month where a daily rate is the fair unit.
- Lease start/end adjustments — when a renewal date shifts and one month ends up partial.
Tips for a Dispute-Free Proration
- Count both end days. Moving in on the 15th and out on the 20th means 6 days, not 5 — the 15th and the 20th both count.
- Use the actual month’s length. A daily rate from a 31-day month is lower than one from February. The tool above uses the real calendar.
- Watch out for February. In a leap year it has 29 days; the calculator picks this up automatically when you select the year.
- Get it in writing. Whatever number you agree on, note the daily rate and the days counted in the lease or a signed addendum.
- Agree on the method first. Some leases use a 30-day standard month instead of the actual calendar — check what yours says.
Frequently Asked Questions
How is prorated rent calculated?
Divide the monthly rent by the number of days in that specific month to get a daily rate, then multiply by the number of days the tenant occupies the property (including both the move-in and move-out days).
Is the move-in day counted?
Yes, by the standard convention both the move-in and move-out days count as occupied days, since the tenant holds the keys on both days.
What if I move in on February 29?
In a leap year, February has 29 days, so the daily rate is monthly rent ÷ 29. Non-leap years use 28 days. This calculator detects leap years automatically from the year you select.
Do landlords have to prorate rent?
Rules vary by state and lease agreement. Many leases specify how partial months are handled, and prorating is standard practice for mid-month move-ins even where the law doesn’t explicitly require it. Check your local regulations and your lease.
What’s the difference between using the actual month and a 30-day month?
With the actual-days method, the daily rate changes with the calendar (lower in 31-day months, higher in February). A flat 30-day method gives one fixed daily rate all year. The difference is small but real — agree with your landlord on which to use.
Can I just enter the number of days instead of dates?
This calculator works from first and last occupied days so the math is transparent and verifiable. If you already know you occupied, say, 10 days of June, enter 1 as the first day and 10 as the last — or any pair that spans exactly 10 days.
Does this include security deposits or fees?
No. The calculator computes rent only. Security deposits, application fees, and utilities are separate charges set by the landlord or lease.
Why is my landlord’s prorated rent different from my calculation?
Almost always one of two things: the method or the day count. The three daily-rate methods can differ by tens of dollars on the same dates, and counting the move-in or move-out day differently shifts the total again.
Is the security deposit prorated too?
No. Only the rent is prorated. Security deposits, application fees, and pet fees are paid in full regardless of the move-in date — they are not payment for days of occupancy. Your move-in total is the prorated rent plus those full charges.
Final Thoughts
A mid-month move is already stressful enough without arguing over rent math. Knowing your exact daily rate and the precise days counted turns a vague disagreement into a one-line calculation both sides can verify. Run the numbers above, save the breakdown, and attach it to your lease paperwork.
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