# How to handle the bills in a shared flat with roommates

> Three or four people, costs nobody uses equally, and someone who always pays for groceries. How to split it without keeping score or fighting over bills.

_Shared expenses · Published 2026-09-02, updated 2026-10-13_

Sharing a flat between three or four people has a problem couples don't: nobody
is willing to pool their money and be done with it. Everyone keeps their own
finances, and yet there's a list of things that get paid for by everybody.

That's where the person who always buys the groceries and never asks for the money
back appears — which is the origin of every flatmate conflict that appears to be
about something else.

## What to agree on day one

Three things, and they take ten minutes:

**What's shared and what isn't.** The simplest rule, and the one that generates the
fewest arguments: **it's shared if it gets consumed without being attributable to
anyone.** Rent, service charges, power, gas, internet, cleaning products, toilet
paper. NOT shared: personal food, one person's delivery, anything for someone's
own room.

The perennial grey area is groceries. Define it explicitly: either there's a shared
basics run — oil, salt, coffee, cleaning — and everything else is individual, or
all groceries are shared. Both work; what doesn't work is never having said.

**How it gets split.** Evenly, by default. With one exception that genuinely earns
its place: **if the rooms are very different, rent gets split by room rather than
evenly.** It's the biggest difference in the flat and the one that breeds the most
resentment if it's ignored.

**Who pays what.** Spread the fixed payments across everyone rather than having
them all leave the same account. It isn't only about fairness: if one person pays
everything and collects afterwards, that person is financing the flat every month.

## The system that works: nobody keeps score

The way this goes wrong is always the same — someone notes things on their phone,
someone else remembers, and at month end there are three versions of the truth.

What works:

1. **One group with the three or four of you**, and each person logs what they pay
   at the moment they pay it.
2. **Fixed costs go in once as recurring.** Rent, service charges, internet: they
   repeat on their own every month and nobody has to re-enter them.
3. **The balance recalculates itself.** Nobody adds anything up; at any point in
   the month you can see who's ahead and who's behind.
4. **Settle on a fixed date each month**, always the same one. Rent day is a good
   anchor.

The four ways of dividing each cost — evenly, by percentage, by shares and by fixed
amounts — are explained in [shared expenses](/en/features/split-expenses).

## The four cases that always cause arguments

**The one who was away for two weeks.** Rent and internet get paid the same: they're
the cost of having the place, not of using it. Shared food isn't. Distinguishing
fixed cost from consumption settles 90% of these arguments.

**The guest who stayed a month.** One night, nothing. Living there, they pay
utilities. It's worth agreeing the threshold before it happens rather than while
it's happening.

**The one who broke something.** Normal wear, shared. Carelessness, on them. If
there's no agreement, shared: a glass isn't worth wrecking the household over.

**The one who leaves early.** Define from day one what happens with the deposit and
the current month. It's the only one of the four that can cost real money.

## When someone falls a long way behind

It happens, and it's almost never bad faith: the debt grew gradually and nobody
mentioned it. Two things help:

- **Keep the balance visible all month**, not just at settle-up. A debt you can see
  on the 10th gets paid on the 10th.
- **An agreed ceiling.** "If anyone goes past a certain amount, it gets settled
  before month end." It's awkward to agree on day one and it prevents the far more
  awkward conversation in month six.

## In one line

Agree on day one what's shared and how it splits, spread the fixed payments across
everyone, log each expense in the moment in a group where the balance recalculates
itself, and settle on the same date every month.

## Download

- iPhone (App Store): https://apps.apple.com/app/id6758053806
- Android (Google Play): https://play.google.com/store/apps/details?id=com.kesef.app

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