The introduction of mobile number portability (MNP) in the Nigerian telecommunications industry has brought a new challenge for mobile operators. This study investigates the use of Analytic Hierarchy Process (AHP) in customer retention decisions in the Nigerian telecommunication industry using a cross-sectional survey design. Primary data were obtained through questionnaires administered to 480 mobile telecommunications subscribers in six tertiary institutions located in Lagos State, Nigeria. These educational institutions were chosen using a multistage sampling technique. Of 438 questionnaires received from subscribers, 408 were valid. Based on this sample data an AHP model was built to assess the determinants of customer retention decisions. Next, eigen values, an eigen vector and maximum lambda (