Similar to the currency exchange of later days, tally worked as follows: one party bought a tally issued by a merchant near the other end to buy merchandise and sent the tally to the other party in advance; the other party requested the issuer to cash the tally he had received, and settled the transaction with money.
後世の為替と同じ様に先に相手先近くの商人が商品購入のために発行した割符を購入して相手先に送り、相手が受け取った割符を発行者に換金を要求してその代金をもって決済する仕組であった。