The rapid growth of digital technologies has transformed customer–brand interactions, especially within Nigeria’s online retail sector where social media platforms have become central to engagement and loyalty-building strategies. This study examined the impact of four key social media engagement tools which include interactive content, real-time communication, user-generated content, and visual storytelling on customer loyalty among online retail consumers in Enugu Metropolis. Guided by Social Exchange Theory, the study adopted a quantitative survey design and collected data from 374 valid respondents through a structured online questionnaire. Descriptive statistics, Pearson correlation, and simple linear regression were used to analyze the data. Findings revealed that all four engagement tools significantly and positively influence customer loyalty, indicating that consumers respond more favorably to brands that provide interactive, timely, authentic, and visually compelling social media experiences. The results further show that real-time communication and user-generated content exert particularly strong effects on loyalty, suggesting the importance of responsiveness and peer-generated trust in shaping consumer attitudes. The study contributes to the growing body of digital marketing literature in sub-Saharan Africa by providing empirical evidence on context-specific engagement determinants of loyalty. It also offers practical implications for online retailers seeking to strengthen customer relationships through strategic social media engagement. The study recommends that brands adopt more interactive, responsive, and visually driven content strategies to enhance loyalty in an increasingly competitive digital marketplace.