How to Prorate Rent (the Right Way)

What prorating means

When a tenant moves in or out partway through a month, they should pay only for the days they actually have the unit. Prorating splits a full month's rent down to a daily rate and multiplies by the number of days occupied.

Three accepted methods

The actual-days method divides the monthly rent by the number of days in that specific month (28–31) and multiplies by days occupied. The 30-day (banker's) method always divides by 30, which is simpler and slightly more predictable. The annual method divides the yearly rent by 365 for the truest daily rate.

All three are legitimate, and the difference is usually a few dollars. What matters is that your lease states which method you use, so there's no dispute. Without a stated method, courts generally expect the actual-days approach.

Put it in writing

Spell out the proration method in the lease and show the math on the first receipt. The prorated rent calculator does all three methods so you can pick one and document the figure.