We analyse corporate tax avoidance in a stylized experimental Bertrand setting withhomogenous products and symmetric firms and consumers. More specifically, we investigate how market size and information disclosure of firms’ tax avoidance behaviour could reduce corporate tax avoidance. We find that making corporate tax behaviour more transparent byimposing a tax rating, makes consumers actively and costly boycott firms that do not pay theirtaxes. Firms anticipate consumer boycotts and increase their tax payments accordingly. Whenrating disclosure is voluntary, the positive effect on corporate tax compliance vanishes in largemarkets.