The mobile network telecommunications sector is rapidly growing in South Africa but research focusing on customer service and customer satisfaction lags behind. Customer satisfaction is critical for brand protection, market share growth and customer loyalty. Research is needed to identify the key aspects which contribute to customer satisfaction. The study investigates whether service quality dimensions (tangibility, reliability, responsiveness, empathy, and assurance), predict customer satisfaction after controlling for customer characteristics namely, sex, age, and education level. A sample of 1451 mobile network users was used. To collect primary data, self-administered questionnaires were used. Hierarchical regression analysis was performed and the results reveal that age and education level had no unique contribution but customers' sex had a statistically significant negative unique contribution to the model. Further, after controlling for sex, age and education level, service quality dimensions, that is, assurance, tangibility, reliability, and empathy had major unique contributions, while responsiveness had a unique minor contribution towards enhancing customer satisfaction experience. The findings are critical to market segmentation practices of mobile network operators as this research indicates that demographic factors play a significant role in ensuring that customer service efforts yield the intended results.