Previous scholarship has suggested that British trade was generally unaffected by foreign tariffs during the period from 1870 to 1913. This article focuses specifically on Anglo‐American trade, which was the largest bilateral flow of trade during the first era of globalization, and finds that tariffs were the sole intertemporal determinant of Anglo‐American trade costs. However, the determinacy of tariffs for Anglo‐American trade costs only becomes apparent when the tariff variable incorporates a measure of the bilateral American tariff toward Britain, which this article reconstructs. The article concludes by claiming that Anglo‐American trade represents a major qualification to any emerging consensus that foreign tariffs were of minor significance to the trade of late nineteenth‐century Britain.