Jars and members

A jar is the unit of shared spending. A trip, a flat, a project — anything where the same group of people is racking up costs and someone has to settle at the end.

Roles

Each jar has exactly one owner — the person who created it. The owner can:

• Add and remove members
• Rename placeholder invitees (people who haven’t yet signed in)
• Change the jar’s default split policy and base currency
• Settle and close the jar

Members can:

• Forward receipts
• See balances and the running ledger
• Edit their own profile

The owner cannot rename a verified member who has personalised their own display name. That boundary exists so one jar’s owner can’t rewrite a profile that’s also visible in another jar.

Default split

When an owner creates a jar, they pick a default split policy. The pipeline applies this when:

• The receipt has no per-line-item attribution
• The forwarded email or receipt body has no split hint

You can override per-receipt at any time. The owner’s default is just the policy when nothing else is specified.

Currency

Each jar has one base currency — usually the owner’s local currency. Receipts in other currencies are converted at the FX rate at extraction time, with a margin that defaults to 2.5%. The original amount is preserved alongside the base.

Settling

When everyone’s added their share and the trip’s done, the owner settles the jar. Splitjar computes the minimum number of transfers between members to balance the books, names them, and the jar closes.

Closed jars stay readable forever — for export, audit, or just looking back.