Knowledge flows and service encounters in digital retail: a bibliometric mapping of cross-buying and customer relationship expansion research (2000–2026)

Purpose This study aims to map the intellectual structure, knowledge flows and thematic evolution of cross-buying and customer relationship expansion research in digital retail and service encounter contexts from 2000 to 2026. Design/methodology/approach A bibliometric science-mapping design guided by the SPAR-4-SLR protocol was adopted. Data were retrieved from Scopus using a TITLE-ABS-KEY search. After applying year, subject area, document type, language and source type filters and removing one duplicate DOI record, the final data set comprised 567 Scopus-indexed journal documents. “Bibliometrix” and “VOSviewer” were used for performance analysis, co-citation analysis, bibliographic coupling, keyword co-occurrence, temporal overlay, thematic mapping and thematic evolution. Findings The field is rooted in customer lifetime value, customer equity, CRM, service quality, satisfaction, loyalty and relationship marketing. Recent research fronts increasingly emphasise digital service quality, customer engagement, e-commerce, omnichannel service encounters, artificial intelligence, machine learning and predictive analytics. Thematic evolution shows a shift from firm-centric customer valuation and retention models toward digitally mediated, experience-driven and analytics-enabled relationship expansion. Practical implications Managers should treat cross-buying as a relationship-expansion outcome shaped by service quality, trust, customer experience, engagement and responsible data use, rather than only as a sales or targeting objective. Originality/value This study positions cross-buying within customer relationship expansion and provides an integrated bibliometric synthesis of its intellectual foundations, research fronts, conceptual themes and future research agenda.