MASLAHAH-BASED APPROACH: INTEGRASI RASIO KEUANGAN, CUSTOMER SATISFACTION INDEX, DAN NPS DALAM MARKET SHARE BANK SYARIAHNIM.: 22303012007Aditya Setiaji WibawaauthorThis study aims to examine the determinants of Islamic banks’ market share in Indonesia by integrating financial performance, customer satisfaction and loyalty, and value-based interpretation within the framework of Maqāṣid al-Sharī‘ah based on Al-Shāṭibī’s approach. The study employs a mixed-methods approach with a concurrent triangulation design, combining quantitative panel data analysis, survey-based analysis, and maqāṣid-oriented normative interpretation as an explanatory layer. Panel data were collected from eight Islamic Commercial Banks (Bank Umum Syariah) over the period 2017–2024, covering Capital Adequacy Ratio (CAR), Financing to Deposit Ratio (FDR), Return on Assets (ROA), and asset-based market share. Panel data analysis was conducted using a fixed effects regression model with the support of EViews software. Primary data were obtained through a survey of 948 bank customers to measure the Customer Satisfaction Index (CSI) and Net Promoter Score (NPS). Survey data were analyzed using SPSS after the measurement instruments were confirmed to be valid and reliable. The results of the panel data analysis indicate that CAR has a positive and statistically significant effect on market share, with a probability value of 0.0031 (p < 0.05), suggesting that capital adequacy plays a substantive role in influencing Islamic banks’ market expansion. Similarly, FDR is found to have a significant effect on market share, with a probability value of 0.0017 (p < 0.05), indicating that the effectiveness of fund intermediation and financing distribution contributes meaningfully to market share growth. In contrast, ROA does not exhibit a statistically significant effect on market share, with a probability value of 0.2108 (p > 0.05), implying that short-term profitability does not directly translate into changes in market share during the observation period. Survey analysis reveals that neither customer satisfaction nor customer loyalty significantly affects market share at the institutional level. The probability value for CSI is 0.8902 (p > 0.05), indicating that high levels of customer satisfaction do not serve as a direct determinant of market share growth. Likewise, NPS shows a probability value of 0.1142 (p > 0.05), suggesting that customer loyalty and recommendation intentions have not been directly converted into aggregate market share expansion. These findings imply that satisfaction and loyalty operate primarily at the relational and behavioral micro level, functioning as mechanisms of customer retention and relationship stability rather than drivers of market expansion. From a Maqāṣid al-Sharī‘ah perspective, the significant influence of CAR and FDR on market share reflects the realization of ḥifẓ al-māl at the systemic level, as emphasized in Al-Shāṭibī’s framework. Meanwhile, customer satisfaction and loyalty represent maṣlaḥah ghayr māddiyyah that supports relational sustainability and social stability, despite not exerting a direct impact on market expansion. The integration of quantitative and qualitative findings leads to the development of a Maslahah-Based Performance Framework, which positions structural performance, relational performance, and maqāṣid-based values as complementary dimensions in assessing the sustainable performance of Islamic banking.297.273 Ekonomi Islam / Fiqih Muamalah2026-08-11UIN SUNAN KALIJAGA YOGYAKARTA;FAKULTAS SYARI’AH DAN HUKUMThesis