How to manage shared household expenses
Household costs are the largest recurring money most people share, and the least suited to being remembered. A system that takes two minutes a month beats one that requires anybody to keep score.
Published
Why this is worth doing properly
Housing is the biggest thing most households spend on. UK households spent an average of £676.60 a week in the financial year ending 2025, and housing, fuel and power was the largest single category at £118.40 a week — 18% of everything.[1]
Split between two or three people, paid by whoever's name is on the account, and repeated every month, that is a substantial and continuous flow of money between people who also have to share a kitchen. It is the highest-stakes shared-money relationship most people have.
Step 1: decide what is shared
The most useful thing you can do is sort every recurring cost into one of three buckets, out loud, before any of them cause a problem.
| Bucket | Typical costs | How to handle |
|---|---|---|
| Definitely shared | Rent, energy, water, council or property tax, broadband, shared insurance | Record every one. These are the large, unavoidable, recurring costs. |
| Definitely personal | Your phone, your subscriptions, your food when you cook alone | Keep out of the shared ledger entirely. Track them in personal records if you want to. |
| Negotiable — decide explicitly | Groceries, cleaning supplies, streaming services, a shared car, guests staying | Whichever way you decide, decide it. These are where friction comes from, and it is always the undiscussed ones. |
Step 2: choose a split method per cost
Household costs divide neatly along one line: does the fair ratio stay the same while the amount moves?
- Percentage for anything shared unevenly on a stable basis — rent by room size, bills weighted by who is home most. Set it once and every future bill divides itself.
- Equal for everything shared evenly. Most utilities, most shared supplies.
- Exact amountsonly for one-offs — a pro-rata month when someone moves in, or a shop where one person's own items are on the same receipt.
Step 3: handle the bill in one person's name
Nearly every household utility is in one person's name and paid from their account. That person is structurally the creditor: they are out of pocket from the day the direct debit leaves until everybody pays them back.
What makes this work
- Record the bill the day it is paid, not at the end of the month. The balance should reflect reality as it happens.
- Record the full amount against the person who paid it, and split it — do not record 'everyone's share' as separate expenses.
- Spread the burden if you can: different bills in different names means nobody is permanently the bank.
- Settle monthly, so the person carrying the cost is never carrying more than one cycle of it.
Worked example: one month of bills, three people
An energy bill of £96 in Kit's name, broadband of £33 in Ren's, and a water bill of £42 in Ivy's. All split equally.
| Bill | Amount | Paid by | Share each | Payer is owed |
|---|---|---|---|---|
| Energy | £96 | Kit | £32 | £64 |
| Broadband | £33 | Ren | £11 | £22 |
| Water | £42 | Ivy | £14 | £28 |
Result: Across all three, each person owes £57 in total and has paid different amounts. Kit paid £96 and owes £57 (owed £39); Ren paid £33 and owes £57 (owes £24); Ivy paid £42 and owes £57 (owes £15). Ren pays Kit £24 and Ivy pays Kit £15 — two transfers for three bills.
Spreading the bills across names, as here, keeps the balances small. If all three bills were in one name, that person would be owed £114 every month.
Step 4: solve the groceries problem
Groceries cause more household friction than rent, despite being a fraction of the cost, because they are frequent, uneven, and partly personal. Three approaches that work:
- Split everything equally and accept it. Simplest, and over months it genuinely does average out. Requires everyone to stop mentally auditing individual shops.
- Shared basics only. Milk, bread, cleaning supplies and staples go in the shared ledger; everything else is personal. Clean line, slightly more admin.
- Split by receipt with own items separated. Use an exact splitwhen someone's personal items are on a shared receipt. Precise, and too much effort to do every week.
Any of these works. Alternating between them, depending on who did the shopping and how they feel about it, does not.
Step 5: settle on a fixed day
Pick a date and keep it — payday, or the day after rent goes out. A fixed day turns settling from a request into a routine, which is the entire difference between a system people keep using and one they abandon.
Households that let balances run for months end up owing amounts large enough that clearing them is its own difficult conversation. Monthly keeps the numbers uncontroversial.
Doing this in Expenddy
Create a group of type Home for the address, add everyone who lives there, and record each cost as it is paid. Percentage splits handle uneven rent, equal splits handle the rest, and the group ledger exports to CSV if you ever need the record outside the app — for a deposit dispute, for instance.
The roommate expenses page walks through a full month with the arithmetic.
Questions
Can I use Expenddy with roommates?
Expenddy works for roommates and flatmates sharing a home. Create a group of type Home, add everyone living there, and record rent, utilities, the internet bill and shared groceries as they are paid. Recurring costs with a fixed ratio can be split by percentage, one-off shared items equally, and anything only some people share can be split between just those people.
Can Expenddy split an expense by percentage?
Expenddy supports percentage splits. You assign each person a percentage of the total, the percentages must add up to 100%, and Expenddy converts them into currency amounts. This suits costs where the ratio stays the same but the amount changes each month, such as rent split 60/40 by room size.
Can I get my data out of Expenddy?
Expenddy exports to CSV. A group's full ledger can be exported from the group's settings, a friend ledger from that ledger's screen, and your personal records from the personal section. The file opens in any spreadsheet program.
Sources
- Family spending in the UK: April 2024 to March 2025. Office for National Statistics, published 11 June 2026 — average total weekly household expenditure £676.60, of which housing (net), fuel and power was £118.40 (18%) — the largest single category
External statistics above are published by the organisations named and are not Expenddy data. Statements about how Expenddy works describe the app itself.