Purpose-In business-to-business (B2B) contexts, innovativeness is often conceptualized as a firm-internal capability reflected in research and development investment, technological advancement and process improvements. This study examines how business customers evaluate supplier innovativeness in B2B service ecosystems and identifies the cues that shape such evaluations beyond innovation outputs or capabilities alone. Design/methodology/approach-The study adopts an abductive qualitative multiple-case design. Empirical material comprises six in-depth interviews with boundary-spanning informants across five innovation-intensive B2B firms, complemented by secondary data. Data were analyzed through iterative coding and comparison within an abductive analytic logic. Service-dominant logic and service ecosystem theory are used as sensitizing lenses. Findings-Customers evaluate supplier innovativeness through observable patterns of action embedded in interaction and coordination practices. These evaluations draw on three interrelated cue clusters: (1) credible enactment of innovation intent, (2) transparency in resource integration and coordination and (3) contributions to ecosystem arrangements that support customer value creation. Combined, these cues form a role-based evaluative frame that customers use while interpreting innovativeness across recurring interaction configurations. Practical implications-Managers can strengthen customer perceptions of innovativeness by making innovation-related practices more transparent, selectively enabling customer involvement and coordinating collaboration across relevant ecosystem actors. Originality/value-This study contributes an empirically grounded perspective on customer-perceived innovativeness in B2B services and develops a role-based framework conceptualized as a co-creation continuum that captures how customers draw on different evaluative logics when assessing supplier innovativeness.