Urban public transport has been developed during the last years, trying to achieve its growth to provide better social, economic and environmental benefits. The reliability of public transport is a key determinant when considering the quality of the service. From a passengers’ perspective, service reliability it’s a key factor to attract and retain passengers in the long term. Since public transport is able to improve and ensure accessibility and livability of cities and since public transport might create a reduction of the negative impacts of increased car mobility, an increase in quality of public transport is necessary. Reliability has been defined from different aspects of bus services in many studies. Buffer time indicators have been the preferred ones to analyze reliability since they reflect passenger-focused attributes. However, passenger’s perception is lost from the time when it takes into account the total travel time. Using AVL system data (automatic vehicle location) and GoCard (automated fare collection) data, which provides the progress of each vehicle as well as passenger loadings, has enabled the analysis of service reliability from the passenger’s perception. All these data was analyzed to make an accurate assessment of the service reliability, comparing different measures. The selected measure was used to investigate the reliability performance for some of the Brisbane bus operations.