Guide · 6 min read
How to split expenses on a group trip
Group trips fall out over money more often than any other reason. The good news: fair splitting is a solved problem — most people just use tools that don't model it correctly. Here's the actual math, and what to look for in a splitter.
Log expenses as you go, not from memory
The single biggest source of arguments is trying to reconstruct who paid for what a week after the trip. Log expenses the same day, ideally within minutes of the receipt. Every expense needs three fields: who paid, the amount, and who it was for.
Exclusions matter — most spreadsheets get this wrong
A typical spreadsheet splits every expense equally across the whole group. That's wrong. If two people skipped the tasting menu, the bill splits four ways, not six. If one person is vegetarian and didn't share the seafood platter, they shouldn't pay for it.
Every expense should let you tag exactly who was involved. Anything less produces a "fair" number that quietly overcharges people who weren't there.
Net at the end — don't settle expense by expense
If Anna paid for dinner and Ben paid for the taxi, don't send two separate transfers. Aggregate everything: total what each person paid, total what each person owes, and the difference is the net balance.
Then minimize transfers: with 6 people you can usually settle everything in 3–5 payments, not 15. A greedy algorithm — biggest debtor pays biggest creditor, repeat — gets you close to optimal.
Direct debt vs. forwarded debt
When the group settles in fewest transfers, the resulting payments don't always match "who ate what". You might end up paying Anna €80 even though you only shared one meal with her — because you also owe Ben €30, and Ben owes Anna €50. The simplification forwards debt through the group.
A good splitter shows both views: the raw pairwise math ("you owe Ben €30, Ben owes Anna €50") and the simplified transfers ("you pay Anna €80"). Both add up to the same total; the second is just fewer bank fees.
Mixed currencies: convert on the day of the expense
When someone pays in euros and someone else in dollars, convert each expense at the exchange rate on that day, not the trip average or the settlement date. Otherwise a strong-dollar day unfairly subsidizes a weak-dollar day.
Settle within a week of getting home
Money memory decays fast. Set a soft rule: everyone settles within seven days of the last flight. Send the exact amounts and a payment link (Swish, Venmo, Revolut) so nobody has to do math or type IBANs.
Built for this
CrewTrip handles all of this automatically
Log expenses with exclusions, see both pairwise and simplified settlements, and settle up with a tap. No spreadsheets, no arguments.