The three-volume set LNCS 15809-15811 constitutes the thoroughly refereed proceedings of the 11th International Conference on Human Aspects of IT for the Aged Population, ITAP 2025, held as part of the 27th HCI International Conference on Human-Computer Interaction, HCII 2025, which took place in Gothenburg, Sweden, in June 2025. The total of 1430 papers and 355 posters included in the HCII 2025 proceedings was carefully reviewed and selected from 7972 submissions. The three volumes cover topics as follows: Part I: Designing Older User Experiences; Social Connectedness and Psychological Support Part II: Smart Homes and Communities for Aging in Place; eHealth for Aging Part III: Older Adults and the (Smart) City; Technology Adoption, IT Literacy and the Digital Divide; Living with AI.