This study explored the implementation effectiveness of FISA (R.A. 10969), reviews and examines the impacts, implementation considerations, and implications of free irrigation services in the Masalip River Irrigation System, particularly within the context of Agoo, Aringay, Sto. Tomas, and Tubao. The NIA personnel particularly the IDO’s have satisfactorily made their duties efficiently for they have helped many farmers in the application of their FISA’s. While they demonstrated commendable performance in daily operations and during field, improvement was needed in by facilitating seminars to farmers to cater for their questions and queries about its scope and policies. The implementation of FISA observed as “highly effective” in delivering water service delivery to farmers it includes monitoring and evaluating its service by gathering feedbacks for its improvement.