Utility bill splitter
Split a shared electricity, gas or water bill by the days each person lived there and, if you have them, sub-meter readings. Shares are exact to the cent and always add up to the bill.
One occupant per line, up to 50 occupants and 100,000 characters; bill periods of 1 to 366 days between 1900 and 2200; each charge 0 to 10,000,000 with 0, 2 or 3 decimal places; meter readings 0 to 1,000,000,000 with up to 3 decimals. Calculated on your device; download a JSON report and CSV files of results and shares. One person per line: name, then optional move-in date, move-out date (YYYY-MM-DD), and sub-meter start and end readings. Up to 100,000 characters. Review the settings before running.
Your result
How to use Utility bill splitter
- Enter the bill period and the fixed and usage charges from the bill.
- List the occupants, with move-in and move-out dates for anyone who was not there the whole period.
- To split usage by sub-meters, choose that option and add each person’s start and end readings.
- Optionally name who paid the bill, then review the shares and download the CSV.
Useful next steps
Person-days
Each occupant counts the calendar days they lived there inside the bill period, move-in and move-out days included. In the example, Ana is there all 30 days of September, Ben from the 11th (20 days) and Cleo until the 20th (20 days), 70 person-days in all. Fixed charges are always split this way.
Sub-meter readings
With sub-meters, usage charges follow each person’s metered usage, the way submetering bills each tenant for their portion (Wikipedia, checked 16 October 2026). Usage on the main bill above the sub-meter total, such as shared rooms, is shared by person-days.
Exact to the cent
Exact shares are rounded once to the currency’s smallest unit with the largest remainder (Hamilton) method (Wikipedia, checked 16 October 2026): everyone gets the whole cents of their share, and the cents left over go to the largest remainders. The 150 example gives 64.28, 42.86 and 42.86, which add up to 150.00 exactly. Equal remainders favour the person listed first.
Limits
Up to 50 occupants, bill periods of 1 to 366 days and charges up to 10,000,000 with 0, 2 or 3 decimal places. Meter readings go up to 1,000,000,000 with up to 3 decimals. This is arithmetic on your numbers, not a reading of tenancy law or tariffs.