PurposeAlthough customer-perceived quality (CPQ) has been studied for years, very little is known about the implications of CPQ to informal retail stores particularly in collectivist and high uncertainty avoidance societies like Nigeria. More specifically, this study aims to investigate the indirect implications of CPQ to post-purchase behaviour primarily word-of-mouth (WoM) communication which is even more critical for customer acquisition in the research context. By so doing, it develops a contextualised model in which the emerging concept of commercial friendship (CF) is incorporated to mediate the relationship between CPQ and WoM communication.Design/methodology/approachUsing a survey-based design, data were gathered from 372 informal merchants’ customers. Structural equation modelling technique primarily PLS-SEM (partial least squares structural equation modelling) was used in analysing the data.FindingsThe data confirm that the multifaceted CPQ construct has an important implication for WoM through the mediation of CF. Supplementary analysis reveals that CF fully mediates one of the sub-components of CPQ, namely, personal interaction in relationship to WoM in addition to acting as a partial mediator between store policy, physical aspect and reliability and WoM.Originality/valueThe value of this study is that it draws attention to the special role that CF plays in the investigation of the relationship between CPQ and WoM communication in the research context. Additionally, it is a step towards extending and contextualising research about service quality perceptions and its outcomes in non-traditional Western contexts.