Success in online retailing depends on effective and efficient last mile delivery. Although online retailing in Kenya has considerable potential to ensure sustainable trade and economic growth, progress in this subsector has been inhibited by several problems. Furthermore, existing literature failed to determine the elements of last mile delivery most valued by online customers and how last mile delivery is implemented by Kenya’s online retail market. Therefore, it is necessary to investigate the elements of last mile delivery in Kenya’s online retail subsector from the perspective of customers and retailers. A convergent mixed methods research design was used to ensure a comprehensive study of the research problem. A total of 407 online customers and seven online retailers in Nairobi participated in providing the required quantitative and qualitative data. The findings indicated that attended home delivery points, same-day delivery lead time, and phone call tracking options are most valued by customers and most offered by retailers. There is, however, a discrepancy in the delivery fee options, delivery timeslots, delivery carriers, and return options most valued by customers, and those most offered by retailers. It is recommended that retailers should review alternative delivery fee options, understand the problem with the outsourced delivery carriers, and the returns process to improve their service offerings.