Prorated rent calculator
Prorated rent is the share of a month's rent you owe for the days you actually live there. Divide the monthly rent by the days in the month, by 30, or by 365 ÷ 12, then multiply by the days you occupy. Moving in on the 20th of a 31-day month at $2,400.00 works out to $929.03, $960.00 or $946.85, depending on the method your lease names.
How do you calculate prorated rent?
Count the days you will occupy the unit in the partial month, counting the move-in day. Then find a daily rate and multiply. The daily rate is the only thing that changes between methods: rent divided by the days in that month, rent divided by 30, or rent times 12 divided by 365. Worked example: rent is $2,400.00 and you move in on December 20, a 31-day month, so you occupy 12 days.
| Method | Formula | Daily rate | 12 days |
|---|---|---|---|
| Days in that month | $2,400.00 ÷ 31 × 12 | $77.42 | $929.03 |
| 30-day month | $2,400.00 ÷ 30 × 12 | $80.00 | $960.00 |
| Daily rate from the year | $2,400.00 × 12 ÷ 365 × 12 | $78.90 | $946.85 |
The gap between the highest and lowest figure here is $30.97. In a 31-day month, dividing by the days in the month gives the lowest figure. In February it gives the highest, and the daily rate from the year gives the lowest: 14 days of a 28-day February at $2,400.00 is $1,200.00, $1,120.00 or $1,104.66. Rounding to the cent can move any figure by a penny.
Which method do landlords use?
Landlords use one of three: the actual days in that month, a flat 30-day month, or a daily rate taken from the annual rent (rent times 12, divided by 365). Leases often name the method in the rent or move-in section, in a line that says how rent for a partial month is calculated. Ask which method the landlord uses before you sign, and check that the first invoice matches it. We know of no California statute that sets a proration method; the lease governs. If the lease is silent, ask the landlord which method they use and get the answer in writing before you pay. If the figure you are quoted matches none of the three methods, ask to see the arithmetic. This is general information, not legal advice.
Is prorated rent due at move-in or the first of the month?
Usually it is due with your first payment, at lease signing or on move-in day, together with the security deposit. Some landlords do it the other way: you pay a full month at move-in, and the prorated amount is added to the second month's rent. That matters when you move in late in a month, because a move-in on the 28th followed by a full rent payment on the 1st means two payments a few days apart. Both arrangements are common and the lease says which one applies. Read the move-in charges on the lease or the move-in statement, and check that the days counted match your actual move-in date. If you move out mid-month, the same arithmetic applies to the last month, but many leases require a full month's rent or a set notice period, so check that section before you plan on a prorated last month.
Can you negotiate the prorated month?
Sometimes. A landlord with an empty unit loses rent every day it sits, so asking for a move-in date a few days later at no charge, or for the partial month to be waived, is a reasonable request on a listing that has been up a while. Free days at the start of a lease are the same arithmetic as free weeks: spread them over the lease and you get the average rent you actually pay, which is what our net effective rent calculator does. Ask in writing, name the days you want covered, and give the landlord something in return, such as a firm move-in date or a longer lease. The landlord can say no. For how to make the ask on the rent itself, see how to negotiate rent. Looking at a specific listing? Paste the link here to see how it compares with nearby asks.
Refreshed 2026-10-31. Every figure on this page is computed from the formulas shown. This is general information, not legal advice; your lease governs how a partial month is charged.