Per head — everyone equal
Every flatmate pays the same share. Simple, transparent, perfect for groceries and everyday purchases.
- Maximum simplicity
- No special rules needed
- Unfair when usage varies a lot
For flatshares · Fair splits · GDPR-compliant
The flatshare app
for fair expense sharing.
Snap your receipts — Bon.line reads every line item, sorts everything automatically and splits costs fairly between you and your flatmates. Per head, by room size or by usage. No more arguments in the WhatsApp group.
✓ No card details needed
✓ GDPR-compliant · Made in Germany
✓ For 2 to 12 people
Money in a flatshare — the silent troublemaker
After cleaning, money is the most common cause of flatshare friction — every long-term flatmate knows the signs. A well-designed flatshare app takes those exact conversations off your plate. Four scenarios from daily flatshare life you'll definitely recognise:
Who bought the loo roll last?
Everyday things like washing-up liquid, loo roll or salt get picked up by whoever happens to be at the shop. Without a tool, that never gets settled cleanly — and someone always ends up annoyed.
Splitting bills fairly
Electricity, broadband, council tax — who pays what? Per head? By room size? By usage? Without a clear rule and tool, this gets renegotiated every quarter.
The Friday night takeaway
"I'll Monzo you later" — and then it doesn't happen. Small amounts add up, and nobody wants to be the one keeping score.
Flatmate moves out — who owes who?
Without clear bookkeeping, every move-out turns into a guessing game: who paid in how much, who's in the red? With a flatshare app: one click, all sorted.
Photo: Vitaly Gariev / Unsplash
Flatshare life, not bookkeeping
Instead of arguing — just hang out.
Who brought the loo roll? Who's turn is it to order the takeaway? Bon.line tracks everything automatically and settles up fairly between you — so the kitchen chat is about the next film night, not about money.
"We had a spreadsheet no one was maintaining any more. With Bon.line it just runs itself — and no one has to play the chasing-up police any more." — Lukas, Nina & Max, 3-person flatshare in Manchester
Three ways flatshares split the kitty
In a flatshare, not everything can be split the same way — rent depends on your room, electricity on usage, food on consumption. A good flatshare app supports all those models in parallel. The three approaches that actually work in practice:
Hybrid — decide per item
Groceries per head, rent by room size, electricity by usage. Everyone pays fairly where it makes sense. Bon.line remembers your default rule per category.
- Maximum fairness
- Works even when someone moves out
- A bit more effort to set up
Shared kitty
Everyone pays a fixed monthly amount into a flatshare pot. That covers all shared expenses — food, cleaning, the gift for the landlord meeting.
- Clear monthly budget
- Works with or without a joint account
- Kitty amount needs occasional adjustments
Bon.line supports all three models — and you can decide individually for every expense how it gets split. The crate of beer can be handled differently from the broadband bill.
How Bon.line makes the flatshare kitty effortless
Three steps, and your flatshare has its shared finances sorted. No more spreadsheet, no more WhatsApp arguments, no more "I just bought loo roll, can someone pay me?" messages.
Snap the receipt
Whoever did the shop — just photograph the till receipt. The AI reads every single line item and sorts everything automatically.
Choose the split
Per head, by room or custom. Bon.line saves your default rule per category and applies it to future receipts automatically.
See the balance
At month-end, the dashboard shows who owes who how much — down to the penny. Settle up with one click.
Flatshare app: Bon.line vs. the alternatives
We've compared the common approaches — WhatsApp group, Splitwise and Bon.line. An honest side-by-side of the features that actually matter in a flatshare.
| Feature | WhatsApp / Spreadsheet | Splitwise | Bon.line |
|---|---|---|---|
| Receipt recognition (per-item) | |||
| Splits per head / by room / by usage | |||
| Up to 12 people per flat | |||
| GDPR-compliant, servers in Germany | |||
| Ad-free | |||
| Categorisation at product level | |||
| CSV export when moving out | |||
| Cost per month (for 4-person flat) | £0 | Ad-supported / ~$3 per head | €8.99 (≈ £1.90 per head) |
Frequently asked questions about flatshare apps
Does our flatshare need a joint account to use the app?
No. The flatshare app works with or without a joint account. Bon.line lets you shop separately and settle up fairly at month-end — everyone sees exactly who owes who what. If you do want a shared account, most challenger banks offer free joint-account options.
How does the app split costs fairly — per head, or another way?
Both work. Groceries and cleaning supplies usually per head, rent and bills often by room size. Electricity can be split by usage. Bon.line allows custom splits per expense and remembers your default rules, so you don't have to decide every time.
What does the flatshare app cost?
Bon.line offers a 14-day free trial, no card details required. The Family plan covers flatshares of 3 to 5 people for €8.99 per month — divided across flatmates, that's under €2 per person. Larger flatshares of 6+ use the Crew plan (€12.99 / month).
What happens when a flatmate moves out?
When someone moves out, Bon.line shows the final balance — who owes who what on the move-out date. The person can be cleanly settled and keeps access to their history via CSV export. New flatmates can be added at any time without losing the history.
Is our data secure and GDPR-compliant?
Yes. Bon.line is developed in Germany, the servers are based in Germany, and all data is processed in line with GDPR. Your expenses are never used for advertising and never shared with third parties.
Does the app work for 2-person or larger flatshares?
Yes. Bon.line scales from 2 people (Duo plan) through 3–5 (Family plan) up to 6+ (Crew plan). Student house, professional flatshare or larger setup — the splitting models and receipt archive work the same. For 2-person flatshares, the household budget for couples page is also worth a look; the model overlaps.
More time for your flatshare — less for bookkeeping.
When the shared kitty runs itself, there's more room for the things that make a flatshare a home.
Try 14 days free →
Photo: Vitaly Gariev / Unsplash