Tier-1 / exact match: invoice number (normalised), amount, and date agree. Tick and move on.
Normalise references: INV-1001 and 1001 are the same invoice. Do not force leftovers into pairs.
Match statement lines to AP lines when invoice #, amount, and date agree. Leave true leftovers unmatched — do not force pairs.
Click a statement line, then click an AP line to pair. Click a pair badge to unlink. Archetypes: S1 × L1.
Drag each leftover into the correct bucket. One is on the statement but not in AP; one is in AP but not on the statement.
Select a card, then click a bucket. Timing and report-flavour mistakes that look like “missing” are critical fails.