The number of activities in city logistics is growing rapidly causing an increase in emissions, and a decline in accessibility and safety in cities. Therefore, the Dutch government has introduced GreenDeal Zero-emission city logistics. The goal of this deal is to have 30-40 of the biggest municipalities in the Netherlands have zero-emission city logistics in 2025. The goal for 2025 is clear, but it lacks a way for municipalities to see their progress and a way to find improvements in their city logistics. This research is focused on developing a maturity model as a tool to assess the maturity level of a municipality for its performance-related city logistics process management to achieve its aim of reaching zero emissions. The City Logistics Maturity Model for Municipality (CL3M) requires a domain-specific, multidimensional model to assess city logistics from a municipal point of view. The model includes six levels (0-5) and a PCDA cycle is embedded throughout the levels. The model is populated through three focus fields (Technical, Social and Corporate, and Policy), branching out into six areas of development: Information and communication technology, urban logistics planning, Stakeholder communication, Public-Private Partnerships, Subsidization and incentivization, and Regulations. The CL3M model was tested for three municipalities, namely, the municipality of Deventer, Zwolle, and Nijmegen. The assessment pointed out that CL3M is yet in its juvenile stage and with further development, the model can reach its full potential in usefulness, reliability, and adaptation@en