This article considers the changing nature of remittance procedures in the eighteenth-century British slave trade. It explains why bills of exchange became the preferred form of making payment for slave sales, rather than specie or produce. It also indicates the legal and institutional practices that informed the circulation of bills of exchange in a notoriously risky form of long-distance trade. The growth and complexity of the British slave trade, which was conducted mainly by private merchants, led to procedures such as remitting bills “in the bottom” of ships that had supplied slaves to North American and Caribbean markets and the extension of lengthy credit periods to purchasers. Colonial factors played a role as well, acting as the agents for coordinating remittances, and secure British merchant houses were deployed as “guarantees” for payment by bills. The development of credit practices associated with the slave trade, including remittance procedures, helped to strengthen the British economy by providing sound, complex intermediary instruments for the realization of profits from international trade.