Trip mode: one group, many expenses, one fair settlement

Holidays, city breaks, road trips, festivals, flatmates. A group in SumFair collects every expense over days or months, in any mix of currencies and payers, and settles it in the fewest transfers.

Groups: who is in and what they can do

A group is a set of people plus a ledger. Both a restaurant bill and a trip are groups; a trip just lives longer.

Create a group
Name, dates, base currency. That's all. The person who creates it is the host.
Add people by link
Share one link or QR code; each person joins with a first name. No accounts, no invitations by email, no app install.
Manage participants
The host can rename or remove a participant, lock the group, regenerate or expire the invite link, and hand over the host role.
Roles
Hosts edit anything and finalize. Participants add expenses they paid for, claim items and mark their own payments; they cannot change totals, payers or other people's shares.
Save and reuse
With a free account: saved groups, favourite people, group preferences, and a duplicate-group action for the next trip.
Every change is logged
“Maria changed the fuel split”, “Tom marked 214.75 as paid”. The audit trail is visible to everyone in the group.

Group screens in the app

Expenses a trip can hold

Manual expense
Taxi 60 EUR, paid by Alex, split equally. The everyday entry.
Scanned receipt
A restaurant bill inside the trip, split by item exactly like restaurant mode.
Several payers
Ski passes: Maria paid 320, James paid 100. Recorded as it happened instead of pretending one person paid.
Expense for a subset
Only three of the five went rafting. The others don't share it.
Transfer
Maria paid Alex 50 EUR in cash. Recorded so balances stay right.
Refund and income
The hotel returned the deposit; a voucher covered part of a dinner. Negative expenses and shared income keep the ledger truthful.

Currencies

Each expense carries its original amount and currency. The trip has a base currency. When an expense is added, SumFair stores the exchange rate it used, where it came from and when; that rate stays attached to the expense forever. A rate can also be entered by hand, for cash exchanged at a kiosk. Balances are shown in the base currency and, on request, in each person's own currency.

Settlement

Balances update after every expense. At settlement, SumFair computes the smallest set of transfers that brings everyone to exactly zero: seven IOUs between four people typically become three payments. You can settle:

  • everything;
  • only until today, for the person leaving early;
  • only selected dates, expenses or people.

Settled expenses are locked into a checkpoint that stores the balances and transfers at that moment. A checkpoint can be reopened with explicit confirmation; SumFair then recalculates and records who reopened it and why. Nothing is edited quietly.

A ski week, worked through

ExpensePaid byAmountIn EUR
Chalet, 5 nightsAlex1 240.00 EUR1 240.00
Ski passesMaria 320, James 100420.00 EUR420.00
Dinner at Gasthof Post, scannedTom186.40 EUR186.40
Fuel, Bucharest to MayrhofenJames1 120.00 RON225.35 at 4.97
Hotel deposit refundto Alex-120.00 EUR-120.00

Without simplification the four owe each other in seven directions. SumFair settles it as Maria → Alex 318.20, James → Alex 241.55, Tom → Alex 214.75. Balances sum to zero; the RON expense keeps its 4.97 rate even if the market moves next week.

Trip and group questions

Do trip members need an account?
No. A trip works like a bill: people join from a link and are remembered on their phone. An optional free account keeps the trip in your history and syncs it across devices.
Can someone join a trip halfway or leave early?
Yes. A person only shares the expenses they were part of, and the host can settle 'until today' for the person leaving while the trip continues for everyone else.
How are exchange rates handled?
Each expense keeps its original currency and the exchange rate at the moment it was added, with the source and timestamp saved. Rates never change retroactively, so totals stay reproducible.
Can I reuse a group for the next trip?
Yes. With a free account you can save the group, its people and its preferences, and start the next trip from it.

Start the group before the trip starts.

Add people by link. They join without an account.