How to split expenses with friends and settle up in the fewest payments
Short answer
Add up what each person paid, work out each person's share of every expense (equal, by shares or exact amounts), then net balance = paid - share. People with a positive balance get money back, negative owe. To settle, repeatedly have the person who owes the most pay the person owed the most; a group of N people never needs more than N-1 payments.
Copy-paste code
Worked example: 3 friends, 2 expenses split equally
Alex paid $90 (groceries), Sam paid $30 (ice cream). Total $120, share $40 each.
Balance = paid - share
Alex: 90 - 40 = +50 (gets back $50)
Sam: 30 - 40 = -10 (owes $10)
Priya: 0 - 40 = -40 (owes $40)
Settle up (largest debtor -> largest creditor):
Priya pays Alex $40
Sam pays Alex $10 -> 2 payments, everyone even
Spreadsheet: share =amount/COUNT(people)
balance =SUMIF(paid_by, name, amount) - SUM(shares of name)Good to know
Round each share to the cent and give leftover cents to the first people, so the shares always add up to the bill.
Different currencies: convert each expense at the rate you actually paid before splitting.
Kittyfern: Split group costs, settle up fast
from $3.99Kittyfern does this in your browser: add who paid, split equally, by shares or exact amounts, and get the fewest-payments settle-up plan and a share link. Free for one group with no daily limit.
Secure checkout · 14-day fix-or-refund if it doesn't work as described (terms)Questions
Uneven split?
Use shares (2 for a couple, 1 for a single) or exact amounts per person; the balance formula stays the same.
Do I need an app?
No. A spreadsheet works; Kittyfern just does the shares, rounding and the settle-up plan for you in the browser, free.
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