BusimyRoommates expenses: how to split rent, utilities and groceries
With roommates the fairest approach separates three kinds of costs: rent (which can be split by room size), utilities and household items (split equally) and personal things (each pays their own). Everyone records what they pay and once a month you settle the difference.
Rent: equal shares or by room?
If the rooms are similar, equal shares. If one has its own bathroom or is much bigger, it is fair that it pays more: for example 40 / 30 / 30 in a three-bedroom flat.
Agree on it before moving in and write it down: it is harder later.
Utilities, internet and household items
Electricity, gas, water, internet, cleaning supplies and things everyone uses: equal shares. If someone works from home and uses much more heating or air conditioning, you can agree on an adjustment.
Groceries
- Each person's own food: their own.
- Shared basics (oil, salt, coffee, paper): equal shares.
- Meals together: among those who eat.
An example with numbers
Three roommates, $3,000 rent split 40 / 30 / 30: Lucy (the big room) pays $1,200, Martin and Sam $900 each. Utilities were $300 this month and Martin paid them: each share is $100, so Lucy and Sam owe Martin $100 each.
How to avoid fights
- Everyone records what they pay, as it happens.
- Everyone sees the same balance.
- Settle up once a month, on a fixed date.
- Personal stays personal: the group doesn't need to see your own expenses.
How Busimy does it
In Busimy you create a household for the flat, invite your roommates and choose the split: equal shares, percentages or fixed amounts, and you can change it on one expense. Everyone records from their phone and the app shows who owes whom.
Three ways to split the rent
Example by size: $1,800 rent, with 60 m² of rooms (30, 18 and 12) and the rest shared. If half the rent goes by size and half in equal parts, they pay $750, $570 and $480.
| Method | How | Best when |
|---|---|---|
| Equal parts | Rent ÷ number of people | Rooms are similar |
| By size | Each room by its square meters, shared spaces in equal parts | One room is much bigger or has its own bathroom |
| By income | Each by what they earn | You're a couple or family, not roommates |
When someone moves in or out mid-month
Prorate by days: whoever leaves pays the days they stayed and whoever arrives the rest. Same with the deposit: the newcomer pays their share to whoever leaves, and the lease isn't touched.
Frequently asked questions
- What happens when someone moves out?
- Whatever is pending gets settled and they leave the household. Earlier expenses stay recorded for everyone.
- What about the security deposit?
- Record it as a debt or a contribution from each one, so that when someone leaves you know how much they get back.
- Are utilities split like the rent?
- Usually in equal parts, since use is similar. If someone works from home all day, you can agree they pay a bit more for power and internet.