Most of the overseas listed firms in the world are cross listed in the domestic market． However, most of the Chinese overseas listed firms are single listed. In this paper，we examine the implicit costs of single overseas listings from the perspective of the information acquisition costs of investors. The theoretical and empirical analysis in this paper show that compared with the cross listed firms, the single listed foreign share has higher informed trading，lower liquidity，and lower prices. Our analysis provides a new perspective in analyzing overseas listings of Chinese firms and the results have direct policy implications on attracting the redchips back to mainland China, especially the launching International Board of Shanghai Stock Exchange．