The paper presents both theoretical and empirical analysis to explain the differences in credit risks between branches and subsidiaries of foreign banks. Using a model with costly monitoring and asymmetric information (from the perspective of host country regulators and parent banks), we show theoretical evidence that the optimal amount of monitoring increases with the size of foreign affiliates (relative to their parent banks), regardless of whether their legal form is of a branch or subsidiary. In the case of small affiliates, we argue that there is a conflict of interest between parent banks and regulators, the former of which prefer to operate with riskier and ring-fenced subsidiaries, and the latter of which prefer better-monitored and co-insured branches. Using bank-level data on Argentina and Uruguay prior to their financial crises of 2001-02, we find that (i) larger foreign branches have lower ratios of non-performing loans than foreign subsidiaries and smaller branches and (ii) branches headquartered in more developed economies had fewer non-performing loans.