Prorated utilities calculator
A roommate moved in or out partway through the billing period? Split the bill by the number of days each person actually lived there.
1. Bill
2. People
Leave dates blank for people who were there for the whole period.
Result
How proration works
Billsplitly counts the days each person lived there during the billing period, counting both the move-in and move-out days. Adding these up gives the total person-days. Each person pays the bill × their days ÷ total person-days, and cents are rounded so the shares add up exactly to the bill.
Want to prorate rent too? Enter the rent as the bill amount. Splitting the rest of your bills? Use the roommate bill splitter or the rent by room calculator.
Other splitting tools
- Roommate bill split calculator
Split rent and recurring bills equally, by income, room size or percentage. - Rent split by room size & features
Weight rent by square footage, private bathrooms, closets and other perks. - Trip & group expense splitter
Track who paid what and settle up with the fewest payments.
Frequently asked questions
Should the move-in day count?
Yes. Both the move-in and move-out dates count as days lived there. If you agree otherwise, just shift the dates by one day.
Is splitting by days fair for internet?
Internet and fixed service fees don't depend on usage, so day-based proration is the usual fair answer. Some households just split them equally for the month anyway.
What if the billing period doesn't match the calendar month?
Enter the exact service period printed on the bill, for example Sep 18 to Oct 17. The calculator works with any period length.
Can I prorate rent the same way?
Yes. Enter the month's rent as the bill and the month's first and last days as the period.