Remittances to developing countries are a sizeable source of foreign financing and have been shown to have a significant development impact. Using newly gathered data across 119 country corridors, this paper explores the factors that determine the cost of remittances. Considering average costs across all types of institutions, we find that corridors with larger numbers of migrants and more competition among remittances service providers exhibit lower costs. On the other hand, remittance costs are higher in richer corridors and in corridors with greater bank participation in the remittances market. Comparing the determinants of costs across all banks and all money transfer operators separately, we find few significant differences. However, estimations for Western Union, a leading player in the remittances business, show that this firms prices are insensitive to competition.