416 © 2023 AESS Publications. All Rights Reserved. Ownership concentration, sustainability practices, and cost of debt: Evidence from ASEAN countries Citra Sukmadilaga 1+ Maria Ervina Permatasari Santoso 2 Erlane K Ghani 3 1,2 Faculty of Economics and Business, Universitas Padjadjaran, Bandung, Indonesia. 1 Email: citra.sukmadilaga@unpad.edu.id 2 Email: mariaervinaps@gmail.com 3 Faculty of Accountancy, Universiti Teknologi MARA Cawangan Selangor, Malaysia. 3 Email: erlanekg@uitm.edu.my (+ Corresponding author) ABSTRACT Article History Received: 18 January 2023 Revised: 29 March 2023 Accepted: 8 May 2023 Published: 19 May 2023 Keywords ASEAN Cost of debt Ownership concentration Public listed companies Sustainability practices. JEL Classification: M20; H69. This study examines the effect of ownership concentration on sustainability practices and the cost of debt. Subsequently, this study examines whether the performance of sustainability practices influences the cost of debt of public listed companies in three ASEAN countries. This study performed a content analysis on the annual reports of 93 public listed companies in Singapore, Malaysia, and Indonesia. The data analysis showed that ownership concentration has a significant negative effect on the cost of debt but no significant effect on sustainability practices. It also showed that there is a significant negative effect of sustainability practices on the cost of debt. Such findings could be attributed to the differences in business relationships between investors and companies and the non-linear relationship between ownership concentration and sustainability practices. This study provides evidence that both ownership concentration and sustainability practices negatively affect the cost of debt of the public listed companies. From the findings, it is recommended that public listed companies should refocus and strategize ways to mitigate the negative effect of ownership concentration and sustainability practices on the cost of debt, particularly in developing countries. Contribution/Originality: This study contributes to the existing literature by being the first to examine ownership concentration and sustainability practices concurrently in three ASEAN countries, focusing on Indonesia, Malaysia and Singapore. 1. INTRODUCTION Over the last decades, ownership concentration has significantly increased due to a major aspect of equity holdings, which is the willingness of owners to decide on long-term or short-term incentives (OECD, 2014). Companies with a more concentrated structure are seen to make up a significant portion of the business landscape (Barontini & Caprio, 2006). In Asia, the most dominant concentrated structure is family ownership, particularly in Japan and Taiwan. The biggest growth in family ownership is seen in companies in the Philippines. Meanwhile, in Southeast Asia, state control is dominant in Thailand, Singapore, and Indonesia, with Malaysia and Hong Kong having the largest growth (Dinh & Calabrò, 2019). In some emerging markets, the largest holdings can reach 50%, whereas the holdings are below 40% in developed markets. High ownership concentration can be a refuge for Asian Economic and Financial Review ISSN(e): 2222-6737 ISSN(p): 2305-2147 DOI: 10.55493/5002.v13i6.4796 Vol. 13, No. 6, 416-430. © 2023 AESS Publications. All Rights Reserved. URL: www.aessweb.com