When friends pay different bills on a trip, a fair split starts with the total each person paid and ends with a short list of transfers.
Start with the shared total
Suppose Alice pays $120 for lodging, Ben pays $60 for groceries and Cara pays nothing. The shared total is $180. If all three agreed to share those two expenses equally, each person’s share is $180 ÷ 3 = $60. Alice paid $60 more than her share, Ben paid exactly his share and Cara paid $60 less. One transfer—Cara pays Alice $60—settles this example.
Enter the agreement, not an assumption
Use FairSpend’s group expense calculator to enter participants and expense amounts. The current tool assumes an equal share across the people you list. Include only costs everyone agreed to share. Personal purchases, refundable deposits and costs owed by only a subset of a group need a separate calculation or a revised agreement before you use the result.
How settlement is simplified
The calculator totals each person’s payments, subtracts an equal share and matches people who owe with people who are owed. It aims to produce a compact set of suggested transfers. Keep receipts or an agreed expense list so participants can verify what was counted. If someone already reimbursed another person, include that in your records before following the new plan.
Rounding and trust
Real payments use cents. With an indivisible cent, participants should agree who pays the extra cent so all transfers add back to the total. The calculator is a planning aid; it does not move money, authenticate a charge or decide what is fair for a group’s circumstances. Review the method and limitations before settling a large bill.
Browse all spending guides · Last reviewed September 22, 2026.