Public transport accessibility assessment evaluates the ease of accessing public transportation services within a specific area. It considers factors such as proximity of stops/stations to key destinations, availability of transportation modes, service frequency and reliability, affordability of fares, and universal accessible infrastructure. Past assessments have focused on similar physical and service parameters. The assessment of public transport accessibility focused primarily on stop-level or corridor-level parameters, neglecting urban-level factors such as land use and building footprints. Additionally, user behavior and perception of public transport accessibility were not considered in most assessment methods. The literature review revealed a lack of a comprehensive framework that integrates public transport accessibility at the urban, corridor, and stop levels. This research aims to develop a framework that addresses this gap by integrating accessibility assessments across these different levels, hence a comprehensive framework for Advanced Public Transport Accessibility Index (APTAI) has been developed in this research. The Urban Network Analysis (UNA) was performed at urban level considering land use and building footprints along with network parameters. At corridor level, the service parameters like frequency, headway, stops, and routes were considered along with dynamic factor of availability of the PT service at the given time and Transit Network Analysis (TNA) was performed. At stop level, Transit Stop Analysis (TSA) was performed to capture the perception and behavior of people about the factors like bus frequency, waiting time, safety, comfort and distance and time to reach from POI (point of interest) to SAP (service access point) was considered, and the transit stop accessibility level was calculated. The APTAI was computed by integrating accessibility indices from each level using an accessibility adjacency matrix. The proposed framework was applied to the case area of Hubli–Dharwad with the results compared against the conventional Public Transport Accessibility Level (PTAL) method.