Young adults between the ages of 18-24 are the loneliest age-group in the UK and other Western countries yet little is known about the causes and experiences of their loneliness. In particular, young adults of lower socio-economic status (SES) living in the most deprived areas are loneliest in the United Kingdom. Therefore, the aim of the data collected included exploring the causes and experiences of loneliness in young adults with these qualities and circumstances from their own perspective (part 1). The data also includes exploration of how these young adults conceptualise and experience their neighbourhood and how they impact upon their loneliness and social connectedness (part 2). This is qualitative data collected from forty-eight participants between June and August 2019 from 48 participants. A recruitment agency was employed to access the quota sample required. Participants were living in/recruited from four of the most deprived boroughs of London, UK: Newham (n = 16), Hackney (n = 16), Tower Hamlets (n = 16), and Barking & Dagenham (n = 16). There were two parts to the study. Part 1 included the free association task, in which participants were first presented with a piece of paper that contained a grid of four empty boxes and asked to express what they associated with “the experience of loneliness” by way of images and/or words. They were further instructed to elaborate one image/idea per box. After completion of the free association task, participants were asked to elaborate on the content of each box, in turn, in an interview. This started with “can we talk about what you have put in box 1, please?” Prompts such as “can you tell me more about that?” were used to ensure thoughts and feelings about the experience of loneliness were fully explored and emerged naturalistically without injection of content via researcher questioning. The interviews lasted for an average of 60 min. Most interviews took place at the participants’ homes though some at a local café, park or similar places if home was not an option. As for part 2, which was immediately after part 1, participants were asked to write or draw one place in their neighbourhood where they feel most socially connected and one where they feel most lonely. Beneath each of the two places they were further instructed to write what it is about that place that makes them feel the way they do. Participants were then asked to elaborate on the content of the association they had produced in an interview. This began with “can we talk about what you’ve put in box one (for the most socially connected place), please?” Prompts including “can you tell me more about that?” and “how does that make you feel in this space?” were used to ensure respondents’ thoughts and feelings about their chosen places were fully explored and emerged naturalistically without input from the researcher questioning. The same process ensued for the second box asking about the loneliest place. Each interview lasted between 20 and 30 minutes. The corresponding image/output for each participant for both parts 1 and 2 is presented.