This study aims to analyze the influence of Islamic financial literacy, religiosity, and trust levels on customer decision-making regarding the use of Islamic banking products among Bank Muamalat customers at the Kuningan branch office. This research is motivated by the rapid development of the Islamic banking industry, yet the level of Islamic financial literacy and inclusion in Indonesia remains relatively low, with a Sharia literacy index of 43.42% and a Sharia financial inclusion index of 13.41%, according to the 2025 National Survey on Financial Literacy and Inclusion (SNLIK) published by the Financial Services Authority. Bank Muamalat was selected as the research object due to its role as a pioneering Islamic bank in Indonesia and its involvement in the Sharia Literacy Movement (GEULIS) program. The Kuningan branch office was selected purposively based on research accessibility and the characteristics of productive-age customers relevant to the community's Islamic financial literacy. This research uses a quantitative approach using Structural Equation Modeling based on Partial Least Squares (SEM-PLS). The research data was obtained by distributing questionnaires to 144 respondents, customers of Bank Muamalat KCP Kuningan, using a simple random sampling technique. Data analysis was performed using the SmartPLS application. The results showed that Islamic financial literacy did not significantly influence customer decision-making (path coefficient = 0.102; p-value = 0.295 0.05). Conversely, religiosity had a positive and significant effect (path coefficient = 0.188; p-value = 0.012 0.05), and trust level had a positive and significant effect on customer decision-making (path coefficient = 0.688; p-value = 0.000 0.05). Trust level was the most dominant variable, based on the highest path coefficient value and an adjusted R² of 0.749 in the model. Customer trust level was the primary factor driving customer decisions in using Islamic banking products, followed by religiosity. Practical recommendations for Bank Muamalat include improving service transparency to strengthen trust, collaborating with religious institutions to enhance religiosity, and integrating sharia literacy education programs with other supporting factors. These findings also provide strategic input for the Financial Services Authority and the sharia banking industry. Penelitian ini bertujuan untuk menganalisis pengaruh literasi keuangan syariah, religiusitas, dan tingkat kepercayaan terhadap pengambilan keputusan nasabah dalam menggunakan produk bank syariah pada nasabah Bank Muamalat KCP Kuningan. Penelitian ini dilatarbelakangi oleh pesatnya perkembangan industri perbankan syariah, namun tingkat literasi dan inklusi keuangan syariah di Indonesia masih tergolong rendah, dengan indeks literasi syariah sebesar 43,42% dan inklusi keuangan syariah sebesar 13,41% berdasarkan Survei Nasional Literasi dan Inklusi Keuangan (SNLIK) 2025 yang diterbitkan oleh Otoritas Jasa Keuangan. Bank Muamalat dipilih sebagai objek penelitian karena perannya sebagai pelopor bank syariah di Indonesia dan keterlibatannya dalam program Gerakan Literasi Syariah (GEULIS), sedangkan KCP Kuningan dipilih secara purposive berdasarkan aksesibilitas penelitian serta karakteristik nasabah usia produktif yang relevan dengan kondisi literasi keuangan syariah masyarakat. Penelitian ini menggunakan pendekatan kuantitatif dengan metode Structural Equation Modeling berbasis Partial Least Squares (SEM-PLS). Data penelitian diperoleh melalui penyebaran kuesioner kepada 144 responden yang merupakan nasabah Bank Muamalat KCP Kuningan dengan teknik simple random sampling. Analisis data dilakukan menggunakan aplikasi SmartPLS. Hasil penelitian menunjukkan bahwa literasi keuangan syariah tidak berpengaruh signifikan terhadap pengambilan keputusan nasabah (path coefficient = 0,102; p-value = 0,295 0,05). Sebaliknya, religiusitas berpengaruh positif dan signifikan (path coefficient = 0,188; p-value = 0,012 0,05), serta tingkat kepercayaan berpengaruh positif dan signifikan terhadap pengambilan keputusan nasabah (path coefficient = 0,688; p-value = 0,000 0,05), dengan tingkat kepercayaan sebagai variabel yang paling dominan berdasarkan nilai path coefficient tertinggi dan Adjusted R² model sebesar 0,749. Tingkat kepercayaan nasabah menjadi faktor utama pendorong keputusan nasabah dalam menggunakan produk bank syariah, diikuti religiusitas. Saran praktis bagi Bank Muamalat mencakup peningkatan transparansi pelayanan untuk memperkuat kepercayaan, kolaborasi dengan lembaga keagamaan guna tingkatkan religiusitas, serta program edukasi literasi syariah yang terintegrasi faktor pendukung lain. Temuan ini juga memberi masukan strategis bagi Otoritas Jasa Keuangan dan industri perbankan syariah.