Persaingan yang semakin kompetitif dalam industri distribusi bahan bangunan menuntut perusahaan tidak hanya menjaga kelancaran distribusi, tetapi juga membangun hubungan jangka panjang guna meningkatkan loyalitas pelanggan. Penelitian ini bertujuan untuk menganalisis peran sales dalam meningkatkan loyalitas pelanggan serta mengidentifikasi faktor-faktor yang memengaruhi peran tersebut pada PT Mitra Maju Mapan Cabang Bondowoso. Penelitian menggunakan pendekatan kualitatif dengan jenis penelitian deskriptif. Data dikumpulkan melalui wawancara mendalam, observasi, dan dokumentasi dengan teknik penentuan informan secara purposive yang melibatkan Branch Sales Manager, tenaga sales, dan pelanggan tetap. Analisis data dilakukan melalui kondensasi data, penyajian data, serta penarikan kesimpulan dan verifikasi, dengan validitas data dijaga melalui triangulasi sumber dan teknik. Hasil penelitian menunjukkan bahwa sales berperan strategis dalam membangun loyalitas pelanggan melalui komunikasi adaptif, pelayanan responsif, komitmen, serta keterlibatan dalam membantu kebutuhan pelanggan. Loyalitas tercermin pada pembelian ulang, rekomendasi, dan keberlanjutan kerja sama. Faktor utama yang mempengaruhi efektivitas peran sales meliputi kualitas pelayanan, citra perusahaan, kepercayaan, dan kepuasan pelanggan. Penelitian ini mengimplikasikan pentingnya penguatan kompetensi interpersonal sales dan konsistensi pelayanan sebagai strategi mempertahankan loyalitas pelanggan secara berkelanjutan. Increasingly competitive competition in the building materials distribution industry requires companies not only to maintain smooth distribution, but also to build long-term relationships to increase customer loyalty. This research aims to analyze the role of sales in increasing customer loyalty and identify factors that influence this role at PT Mitra Maju Mapan Bondowoso Branch. The research uses a qualitative approach with descriptive research type. Data was collected through in-depth interviews, observation and documentation using purposive informant selection techniques involving Branch Sales Managers, sales personnel and regular customers. Data analysis is carried out through data condensation, data presentation, as well as drawing conclusions and verification, with data validity maintained through triangulation of sources and techniques. The research results show that sales plays a strategic role in building customer loyalty through adaptive communication, responsive service, commitment, and involvement in helping customer needs. Loyalty is reflected in repeat purchases, recommendations and continued cooperation. The main factors that influence the effectiveness of the sales role include service quality, company image, trust and customer satisfaction. This research implies the importance of strengthening interpersonal sales competence and service consistency as a strategy to maintain customer loyalty on an ongoing basis.