In urban areas, informal green spaces (IGS) can offer complementary green resources next to designed parks and gardens, contributing to green space equality. Therefore, particular attention should be paid to what cultural ecosystem services (CES) IGS provide in socioeconomically deprived neighbourhoods. However, how residents of these neighbourhoods perceive IGS and how IGS can serve as an everyday social space is still an under-explored area. This research investigates local residents’ perception and preference of CES provided by an IGS in Amsterdam K-buurt through semi-structured interviews. The interview data were processed through five thematic groups including human scale, recreational and social activities, adequate amenities, inclusivity and accessibility, and appropriation, revealing two dynamic networks of CES perceptions and preferences. Positive perceptions centred on recreational activities like play and dog walking, while challenges included inadequate amenities, poor maintenance, and a sense of neglect. Suggestions emphasised enhancing amenities, fostering community-focused programmes, improving human scale by defining borders, and creating opportunities for appropriation to make the space more inclusive and engaging. By diving into qualitative perspectives, the paper reveals the social dynamics in IGS and highlights the design potential for IGS to contribute to the livability of local environments.