This book constitutes the proceedings of the 30th International Conference on Formal Methods for Industrial Critical Systems, FMICS 2025, held in Aarhus, Denmark, during August 27–28, 2025. The 13 full papers included in this book together with 2 invited papers were carefully reviewed and selected from 25 submissions. The papers have been organized in the following topical sections: verification; automotive and railway; cyber-physical systems; and embedded systems