Utility split by size and occupants.

Worked example

A 240.00 bill is split 50% by occupants and 50% by area across three units: Unit A has 700 sq ft and 3 people, Unit B 500 and 1, Unit C 800 and 2. Totals are 2,000 sq ft and 6 occupants. Unit A pays 240 x (0.5 x 3/6 + 0.5 x 700/2000) = 102.00, Unit B 50.00 and Unit C 88.00. Set the occupant weighting to 0 for a pure area split (84.00 / 60.00 / 96.00).

How it works

Share = bill x (occupant% x occupants / all occupants + (1 - occupant%) x area / all area). At 100% every person pays the same; at 0% it follows floor area only. Use the same area unit for every unit. The shares are rounded to the cent and add back to the bill. There is no standard weighting, so agree the percentage with everyone first; a common rule of thumb, not a published standard, is to weight occupants more for water and area more for heating.

Sources and basis (checked 2026-10-08): arithmetic on the numbers you enter, with no external constants or published figures. Amounts are in whatever currency you enter. This is a calculation aid, not legal, tax or financial advice.

FAQ

How do I split a utility bill by square footage?

Divide each unit area by the total area and multiply by the bill. Set the occupant weighting to 0 in this tool for a pure area split.

Should I split by area or by number of people?

Heating and cooling tend to follow area while water follows people, but there is no single standard. This tool lets you blend them, such as 50 and 50, and you agree the blend in advance.

What unit should I use for area?

Square feet or square metres, as long as every unit uses the same one.

Can a landlord bill tenants this way?

This tool does the arithmetic only and is not legal advice. Whether a shared bill may be passed on, and how, depends on your lease and local rules.

How is it different from the utility bill splitter?

The utility bill splitter uses days at home or measured usage. This one is for units or rooms on one meter where the split follows size and headcount.