After the 2008–2009 financial crisis, there was an increase in prudential measures to limit banking and systemic risk in several countries. The empirical studies related to this topic have focused, in general, on assessing the effectiveness of such instruments. This article addresses the associated costs (adverse effects) of these prudential measures on banking competition. We use a novel approach that employs a stochastic frontier model to measure Brazilian banks' mark-up and estimate the impact of prudential measures on market power. Our results suggest that the tightening of prudential measures increases banks’ mark-up and, consequently, has a negative impact on banking competition. Our finding suggests that financial regulators should consider this adverse effect when designing regulations to promote financial stability without harming competition in the banking system.

在2008年至2009年的金融危机之后，一些国家采取了更加审慎的措施来限制银行业和系统性风险。与该主题相关的实证研究通常集中于评估此类工具的有效性。本文讨论了这些审慎措施对银行业竞争的相关成本（不利影响）。我们使用一种新颖的方法，该方法采用随机前沿模型来衡量巴西银行的加价幅度，并评估审慎措施对市场支配力的影响。我们的结果表明，审慎措施的收紧会增加银行的加价幅度，从而对银行业竞争产生负面影响。