The primary objective of this study was to assess the English proficiency of teachers and its correlation with the academic achievement of fourth-year high school students in Surigao City and Surigao del Norte Divisions, with the ultimate goal of informing a proposed faculty enhancement program. Specifically, it examined teacher profiles—educational qualification, teaching experience, continuing education, and efficiency rating—and assessed their English proficiency in listening, speaking, reading, writing, grammar, and literature. Students’ performance in the same skills was also evaluated. The study employed a descriptive-correlational design, involving 32 English teachers and 381 students from 30 mainland high schools, which were selected using Slovin’s formula and stratified random sampling. Data were gathered using the Regional Unified Test (REUNITE) and a researcher-developed profile survey, and analyzed using means, standard deviations, Pearson correlations, and t-statistics. Results revealed that both teacher and student performance in English skills were at an average level, with literature and grammar identified as the weakest areas. A significant positive correlation (r = 0.75, p < 0.05) was found between teachers’ English proficiency and their teaching experience, suggesting that expertise enhances instructional skill. However, no significant relationships were found between teacher proficiency and educational qualification (t = 1.389), continuing education (t = 0.6111), or efficiency rating (t = 1.167). Likewise, there was no significant correlation between teacher proficiency and student achievement (r = 0.30, t = 1.765). These findings suggest that while experience influences teacher proficiency, other variables may also independently impact student achievement. The study recommends targeted professional development interventions focused on reading and literature instruction to strengthen both teacher effectiveness and student outcomes.