Abstract-Continuing proliferation of wireless devices exposes humanity to the reality of the twin challenge posed by finite frequency spectrum and almost infinite demand for the same frequency spectrum, necessitating the need for more ingenious spectrum management techniques. The band 2.4-2.7 GHz was originally created and classified for ISM, 3G, UMTS and WiMAX systems. It has become a frequency band which is generally used by end users due to the fact that it's inexpensive, easy to deploy and enhances frequency re-use. Quite a few measurements have been carried out in countries like France, Germany, India, Romania, UK and USA. This paper presents a study of an outdoor measurement on spectrum occupancy in both rural and urban areas in Kwara State, Nigeria, spanning across the frequency range of 2.4 GHz -2.7 GHz. The results show that the band being investigated is immensely underutilized with upper and lower occupancy values of 22.56% and 0% in urban and rural environments. These results were compared to other measurements conducted globally in this band or closely aligned bands.Index Terms-ISM band, spectrum occupancy, spectrum utilization, UMTS network.