Using administrative data linkage, this paper sought to quantify the impacts of family homelessness on pupil absence from school. It addresses a gap in United Kingdom (UK) homelessness research, which draws predominantly on qualitative methods and where there is a greater focus on people who fall outside of the statutory system, i.e., single people living on the streets, rather than families. Education records for the academic years 2012/13 to 2015/16 relating to pupils aged 5 to 15 years old living in a coastal city in Wales, UK, were linked to data on households assessed by the statutory housing service operating across the same region. Analysis of mean half-day sessions absent from school, and Poisson panel regression were used to explore associations between absenteeism (authorised, unauthorised, and total), and whether pupils were living in a household making a statutory homelessness application, i.e., experiencing family homelessness. On average, in any given academic year, pupils experiencing family homelessness (PEFH) missed 5 days more of school than pupils not experiencing family homelessness (PnEFH). Adjusted regression analysis found that the rate of total absence was 7% higher amongst PEFH compared to PnEFH, whilst for unauthorised absence it was 13% higher. When a student experienced family homelessness, this led to an increase in their rate of total absences by 5%—adjusting for other factors—compared to when they were not homeless. Findings have implications for statutory education and housing provision, specifically the need for greater cross-disciplinary working to prevent and alleviate the harms caused when families experience homelessness.