Protected areas (PAs) are expected to provide multiple ecosystem services (ESs), but quantitative assessments on their effectiveness in maintaining ESs are often lacking. This work aims to assess the effectiveness of PAs in delivering multiple ESs compared to non-protected areas (NPAs), while exploring trade-offs and synergies between ESs and their hotspots. To this end we quantified, mapped and analysed four forest-related ESs in a mountainous region of northeastern Italy, which includes several PAs of the Natura 2000 network. We found higher values of habitat provision and recreation supply ESs in PAs than in NPAs, but lower C storage and erosion control. No extreme trade-offs between ESs were observed, and hotspots were identified both inside and outside PAs. Our results suggest that landscape composition in terms of land use and cover as well as geo-climatic characteristics greatly influenced PAs’ and NPAs’ ability to provide ESs.