Rent split calculator
Bigger rooms pay more. Enter the rent, the bills and each room's size to see a fair split, or split everything evenly if the rooms are much the same.
How this is calculated
Split by size, each room pays the rent in proportion to its floor area. A 14 m² room in a house with 34 m² of bedrooms pays 14/34 of the rent.
Split evenly, the rent is divided by the number of people, so a couple sharing a room pays two shares.
Shared bills are always split per person, because use of heating, water and broadband depends on people rather than room size.
Leave unused rooms blank, with no size and no people, and they are ignored.
Rates used · 2026/27
| Rent | split by floor area or per person |
| Bills | split per person |
| Rooms | up to six |
| Couples | count as two people |
Last checked July 2026. Source: HMRC and gov.uk.
Worked example
£2,400 of rent and £300 of bills shared between rooms of 14, 11 and 9 m² comes to £1,088.24, £876.47 and £735.29 a month. The rent follows room size, and the bills are £100 each.
Common questions
What is the fairest way to split rent?
Most people find splitting by room size fairest when rooms differ a lot, and splitting evenly simplest when they are similar. Some add a fixed premium for an en suite or a parking space first.
How do I measure a room?
Multiply the length by the width in metres. Measuring the usable floor is enough; it only needs to be consistent between rooms.
Should a couple pay double?
For rent split by size, the room's share is the same however many people sleep in it. For bills, a couple usually pays two shares, because two people use more.
Who is responsible for the rent?
On a joint tenancy every tenant is usually liable for the whole rent, not just their share. If one person stops paying, the landlord can ask the others for it.