Split trip costs where the trip already lives
Attach costs to the bookings they belong to, mark which are per person and which are for the group, and settle up across currencies at the end. Because the costs sit on the itinerary rather than in a separate app, you can see what a day costs while you are still deciding whether to do it.
Costs attached to the thing you booked
A cost belongs to something: the flight, the apartment, the boat trip, the hire car. Recording it against that item means the number and the plan stay together — you can look at Thursday and see what Thursday costs, rather than looking at a list of amounts and trying to remember which was which.
It also means the total is not a separate act of bookkeeping. As the itinerary fills in, the trip totals by category, so the budget is a by-product of planning rather than a spreadsheet you keep meaning to update.
Per-person costs and whole-trip costs are different things
A museum ticket is per person. An apartment is not. Treating them the same is how a shared budget quietly becomes wrong, so each cost is marked as one or the other and the totals respect the difference.
The per-person split divides across everyone on the itinerary. If someone is on the trip for planning purposes but is not paying, that is worth knowing before you rely on the split — the division is by who is on the trip, not by who is travelling.
Multi-currency, without a spreadsheet
On any trip that crosses a border, people pay in whatever the local currency is, on whatever card happened to be in their pocket. Costs are recorded in the currency they were actually paid in rather than converted at the point of entry and then argued about later.
The settle-up resolves the whole set at the end. This is the part that is genuinely uncommon: bill-splitting apps handle multiple currencies, and trip planners handle costs, but the two together — inside the itinerary — is where most tools hand you back to a spreadsheet.
A worked example
Three of you go to Japan via Singapore. You pay ¥180,000 for the apartments. Sam pays S$420 for the stopover hotel. Alex pays ¥64,000 for the rail passes and £150 for the airport parking at home.
Rather than four reimbursements crossing in opposite directions, settle-up nets the whole thing down and names the smallest set of payments that clears it — usually one or two transfers instead of six.
Settling up in the fewest transfers
The naive way to settle a group trip is for everyone to pay everyone back for each thing. With four people and a dozen shared costs that is a lot of small transfers, several of which cancel each other out.
Settle-up works out the net position of each person and then the minimum set of payments that squares everyone. You get told who pays whom and how much, once.
Should you just use a bill-splitting app?
Honestly: if all you need is to split a set of expenses between people, a dedicated bill-splitting app is very good at that and you should use one. Splitwise and tricount have been doing it for years and have features this does not.
The case for doing it here is narrower and specific. If the trip itself already lives in an itinerary — the flights, the stays, the activities, the days — then the costs are already attached to things you have entered, and keeping them in a second app means entering everything twice and reconciling two versions of the same trip.
Questions people ask
Can people pay in different currencies?
Yes. Each cost is recorded in the currency it was paid in, and the settle-up resolves across them at the end rather than making you convert as you go.
How does the per-person split work?
Mark a cost as per person and it divides across everyone on the itinerary. Costs that are for the whole group — an apartment, a hire car — are marked that way instead and are not multiplied.
Does everyone need to pay for the app to split costs?
No. The cost planner, the split and settle-up are all free, for everyone on the trip.
Can I hide the costs when I share the itinerary?
Yes. Publishing a read-only link has an option to leave costs out, so you can share the plan without the prices.
Does it work offline?
Reading costs and totals works with no signal, and edits queue and sync when you reconnect. Full offline access is a Pro feature.
Stop reconciling two apps
Put the costs on the itinerary that already has the bookings in it, and let the settle-up do the arithmetic at the end.