This book constitutes revised selected papers from the 26th International Symposium on Trends in Functional Programming, TFP 2025, held in Oxford, UK, during January 13–16, 2025.

The 20 full papers and 2 invited papers presented in this volume were carefully reviewed and selected from 35 submissions. They were categorized under the topical sections as follows:Invited papers; Language Design; Compilation; Semantics; Types; Program Synthesis; Teaching.