The paper refers to the social innovation of participatory budgeting which has become a very popular tool for stimulating citizen participation at the local level in Poland. It focuses on the major cities, defined as capitals of the voivodeships or regions. Based on the data concerning 2018 participatory budgeting editions in the eighteen cities, it describes the funding, organisation of the process, forms of voting and voter participation as well as the nature of projects selected and implemented. According to the amended Act on the Local Self-Government, organisation of participatory budgeting will only be obligatory for Polish cities from 2019. Despite that fact, it has already become quite popular and broadly applied in local communities. However, citizens’ participation and involvement in the process seems quite low, suggesting a need for experience sharing and improvement of the initiative. Also, project selection reflects the influence of various social groups within urban communities, rather than assisting groups which are at risk of marginalisation.