Mapping accounts & the sign principle

Mapping is the once-per-account decision of where a source account lands on your statements.

Where to map

The batch page's Accounts in this batch panel is the working surface: every account, its amount, its status. Bulk-select rows that share a destination. The Statement Mapping page has the same controls plus the structure editors, and is where you fix an existing mapping (re-saving an account's code overwrites it).

Signs — you mostly never think about them

Larch infers polarity from the statement and the line's section. The one exception control is the checkbox "amounts arrive inverted from the source" — for accounts the source reports upside-down (classic case: an interest-expense account that lives under an income heading in the source's chart). The live preview under each row shows the result before you save: "shows as $6,295.00 on Direct Labor — reduces profit." If the preview reads wrong, the mapping is wrong.

The principle behind it (for debugging)

Two signs exist in the data: the mapping sign normalizes how the source delivers the number; the line behavior says what the line does to the statement. An expense showing positive but adding to profit means the two signs cancelled — flip the mapping (usually via the inverted checkbox), never by fighting the line behavior.

Special cases

• P&L accounts in a trial balance map to the equity line Current Year Earnings — that's what makes a TB balance.
• Expense credits (refunds) display negative under their expense heading and add to profit — correct, leave them.
• Ignore is for true noise (clearing/suspense accounts) — ignored accounts still commit as facts but never reach a statement.