This study designs a customer value co-creation model for the gas industry, with a focus on Iran's gas industry, an infrastructure-based and monopolistic setting in which customers are typically treated as passive recipients of service and for which no indigenous, evidence-based model has been proposed. The study reports the qualitative phase of an exploratory sequential mixed-methods project. Thematic analysis was applied following the thematic network approach. Semi-structured interviews were conducted with 15 experts (nine marketing and management faculty members and six gas-company managers and deputies) selected through purposive and snowball sampling until theoretical saturation. The data were analyzed in MAXQDA 2024 through open coding, sub-theme formation, and main-theme formation. The 203 coded segments were organized into 65 indicators (basic themes), 21 sub-themes, and seven main themes: technological and digital infrastructure; customer engagement and participation; service quality and customer experience; customer-centric organizational culture; communication and information transparency; co-innovation and joint value creation; and co-created shared value as the model outcome. Cohen's kappa for coding agreement was .802, and no new codes emerged after the fifteenth interview. The final model portrays value co-creation in the gas industry as a multilevel process in which six driver themes (technology, engagement, quality, culture, transparency, and co-innovation) lead to co-created functional–economic, relational, and experiential–social value. The model provides a conceptual basis for quantitative testing and a planning framework for gas-company managers. Based on the literature reviewed, this is the first indigenous, data-driven co-creation model for an infrastructure industry with a monopolistic, quasi-governmental structure.