Prorated Utilities Calculator

Use our Prorated Utilities Calculator to split a utility bill fairly between housemates who lived there for different parts of the billing period — when someone moves in or out mid-cycle, or is away for part of the month.

The bill is shared by person-days: each person’s days in the house, divided by everyone’s days added together. For example, with a $120 bill for 30 days, two people who were there the whole time and one who moved out after 10 days have 70 person-days between them, so the two long-term housemates pay $51.43 each and the one who left pays $17.14 — about $1.71 per person per day.

If the home stood empty for some of the period, enter those days too: their share of the bill is set aside for whoever covers an empty home, and the rest is split. A single tenant who stayed 10 days of a 30-day, $120 bill, with the other 20 days empty, pays $40.

This assumes each person uses about the same each day; it doesn’t measure who used more. Agree on the method with your housemates and treat the results as an estimate. To prorate a bill for one person’s days, use our Prorate Bill Calculator; to split the rent by room size, our Room Rent Calculator.