Two bedrooms, one en-suite: a fair split
The en-suite is the whole difference between these rooms for most people. Decide what it’s worth as a multiplier, and the rest follows from floor area.
Kitchen, living room, shared bath. The rest of the rent follows each room.
Closet, light, noise
Closet, light, noise
Weights you agree on
The link holds the whole split. Nothing is stored on our server until you make it a household.
The working, room by room
| Room | People | Weight | Shared part | Room part | Pays |
|---|---|---|---|---|---|
| En-suite | 1 | 180 × 1.3 | $367.50 | $877.50 | $1,245.00 |
| Hall bath | 1 | 130 × 1 | $367.50 | $487.50 | $855.00 |
| Total | 2 | $735.00 | $1,365.00 | $2,100.00 |
Weight = floor area × the room’s multiplier (private bath and factors). Unrounded parts are shown; the “Pays” column is rounded to cents so it adds up exactly.
The numbers, step by step
Two roommates split $2,100. The en-suite room is 180 sq ft; the other room is 130 sq ft and uses the hall bathroom, which guests also use. They count 35% of the rent as shared space and value the private bath at 1.3× the room’s floor area.
- En-suite pays $1,245.00: private bath (×1.3), 1.16× average floor area.
- Hall bath pays $855.00: 0.84× average floor area.
- Total: $2,100.00, exactly the rent.
Names and amounts are samples. Change any number in the calculator above and the result updates.
A fairness test you can run together
Fair-division research calls a split envy-free when each person feels they got the best piece “in her own estimation”, as Francis Su puts it. Ask: at these prices, would anyone rather swap rooms? If not, nobody envies anyone. Bid mode makes that a guarantee.
Keep it running
Turn this into a household: rent posts at the agreed split each month, bills split by days home, and housr works out who owes whom. Roommates join with a link and a name.
Make it a householdWhen this split is fair, and when it isn’t
Fair when
- The person in the hall-bath room really does share their bathroom with guests and the other roommate on busy mornings.
- You both agree on the multiplier before choosing rooms. A useful test: would each of you be happy to take either room at the computed prices?
- Shared space is kept at a lower percentage because the flat has little common area besides the kitchen.
Not so fair when
- If the en-suite is tiny or has no shower, a 1.3× multiplier is too generous; try 1.1.
- If the hall-bath person never has guests and the master’s occupant often uses the hall bath anyway, the private bath is worth less than it looks.
- If one of you works from home in your room all day, consider the space-use argument separately from the bathroom argument.
This is general information about splitting costs between yourselves, not legal advice. Your lease and your state’s law decide what you owe the landlord.
Sources
- Spliddit, Assign Rooms and Share Rent. Checked 2026-10-05.
- Gal, Mash, Procaccia and Zick, Which Is the Fairest (Rent Division) of Them All? (J. ACM 64(6), 2017). Checked 2026-10-05.
- Francis Su, Harvey Mudd College, Fair Division Calculator (historical page). Checked 2026-10-05.
Related situations
How much more should the master bedroom pay?
A private bathroom and roughly twice the floor area are worth something to whoever gets them. Price both openly, so nobody quietly subsidises the bigger room.
Open the example Split rentBid for rooms so nobody wants to swap
Instead of arguing about what a bath or a window is worth, each person puts a price on each room. The result gives every room to someone who values it, at prices nobody envies.
Open the example Split rentOne roommate pays the landlord. Who sends them what?
Many landlords take one payment. Whoever sends it is fronting money for everyone, so make the amounts exact and the record shared.
Open the example