We investigate the welfare implications of banning the no‐surcharge rule (NSR) in credit card markets. In particular, we introduce a governance mechanism alteration and merchants' heterogeneity into the model of Wright (2003). In doing so, we find two market forces exist in the transition of lifting the NSR. The first force is the classical double marginalisation because of merchants being able to deliberately impose a surcharge. The second force arises from a market structure change that merchants, who did not accept credit cards payments, do accept afterwards. Our model shows that the welfare implication hinges on the relative magnitudes of both market forces. More importantly, this article provides an explanation for the surcharging behaviours of merchants in Australia after the removal of the NSR in 2003, which have not been explained in the literature.

中文翻译：

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信用卡市场中的免附加费规则和附加行为

我们研究了在信用卡市场上禁止无附加费规则（NSR）对福利的影响。特别是，我们在赖特（2003）的模型中引入了治理机制的改变和商人的异质性。通过这样做，我们发现在解除NSR的过渡过程中存在两个市场力量。第一力量是经典的双重边缘化，因为商人能够故意施加附加费。第二种力量来自市场结构的变化，不接受信用卡付款的商人事后会接受。我们的模型表明，福利含义取决于两个市场力量的相对规模。更重要的是，本文对2003年NSR取消后澳大利亚商人的收费行为进行了解释，