This study assessed teachers' self-efficacy and students' competencies in online-based instruction in Claveria East District, Philippines. Teachers' self-efficacy was evaluated across dimensions like technological resource selection, virtual interaction, content migration, class alignment, and web-based structure. Data from 145 secondary school teachers (both public and private) were collected using a survey questionnaire with sections on personal/professional information, student competencies, teachers' self-efficacy, and continuance intention. Results indicated very high self-efficacy among teachers, average student competency levels, and strong intention to continue using online instruction. Recommendations include enhancing technology, supporting policies, employing diverse teaching strategies, and ensuring reliable internet and technical support to optimize online instruction effectiveness.