Despite evidence on the benefits of mentoring with beginning teachers, little is known about the impact of mentoring on experienced teachers. Based on a qualitative research design, this study explores mentoring with 11 teachers of English as an additional language (four mentors and seven mentees) during the COVID-19 epidemic. Data were gathered through mentees’ journals, interviews, and documents. Drawing on thematic analysis, mentees were found to improve their teaching practice and develop their professional knowledge. Specifically, they displayed more sensitivity to learners, unleashed creativity, improved class management, strengthened relationships, increased motivation, and developed reflective competencies. The study argues that mentoring can allow all English language teachers to build knowledge with other teachers from their own experiences and for other teachers and educational stakeholders.