PurposeThis paper aims to examine the influence of formal and informal institutional quality on country-level variations in foreign equity shares in transition economies (TEs).Design/methodology/approachDrawing on institutional theory and transaction cost theory, this paper examines the influence of formal and informal institutional quality on country-level variations in foreign equity shares in TEs. The authors use a two-step empirical strategy, identifying clusters of explanatory variables and running generalized least squares random effect estimations to test for the influence of explanatory and control variables on foreign equity shares.FindingsForeign equity share is positively affected by informal institutions and negatively by formal institutions. However, when control for stage of transition we find that the the presence of informal institutions in more rapidly or advanced transforming economies negatively influences foreign equity shares. Complex infrastructure discourages foreign equity shareholdings, and foreign companies use informal practices to overcome unfavourable host country conditions. Government size has a negative effect, and gross domestic product per capita positively affects foreign equity shares.Research limitations/implicationsThe study is the new groundwork for the re-enactment of a fruitful discussion on foreign equity. The study has practical implications for managers, too – managers of foreign-owned firms operating in weakly installed institutional environments should carefully analyse the entry strategies because of the high presence of informal institutions. Furthermore, managers could understand the various facilitation roles of informal institutions in any firm internationalisation effort to arrive at optimal ownership holdings for better internationalisation performance. Although the study is based on a sample of transition countries, the findings have implications for other emerging economies’ contexts sharing similar institutional settings.Originality/valueThis study provides a unique empirical investigation and evidence based on country-level indicators on the effect of formal and informal institutions on foreign equity shares holdings in TEs, reinforcing the importance of impacts of both the formal and informal dimensions on ownership decisions of foreign investors.