The quality of public transport is essential for the adoption of a more sustainable and inclusive urban mobility. Only investments in the quality of these systems will allow individual motor vehicle users to consider the system on their journeys, as well as provide a better level of service to those who depend on the system daily. The objective of this article was to evaluate the quality indices in urban bus transport in the city of São Paulo and to present how these indicators can be grouped to facilitate operators to meet the levels of quality in service proposed by São Paulo Transporte S/A, manager company of the system. Thus, the article uses the statistical technique of factor analysis to make this grouping based on the results presented by the operators in May 2022. The results showed that the 10 quality indicators could be grouped into only three main ones: quality of the operation of transport, safety of the transport operation and quality of the maintenance service, thus facilitating the quality assurance work of the operators and greater satisfaction of the population that uses the system.