The article presents results of studies in Chile and Portugal during COVID-19 lockdowns and remote teaching conditions. In each of both countries, over two thousand teachers of all school levels and types were surveyed during a two-month period on their professional experiences in the first year of remote teaching. The article discusses teacher accounts of how their work changed, their difficulties, impact on well-being, as well as new professional learning brought about by the challenges involved. Conceptually, the study relied on notions of occupational professionalism, self-efficacy perceptions and collegial support in challenging circumstances. Results in both countries highlighted an impact on teacher occupational professionalism and self-efficacy perceptions, mainly brought about by intermittent levels of engagement of students during remote teaching sessions, and difficulties in carrying out proper assessments of student learning. Student well-being was of greater concern to teachers than their own problems, despite feeling the stressful effect of much longer daily working hours, more so among Chilean than Portuguese teachers. The study also brought out teachers' imaginative efforts and the use of unaccustomed pedagogic strategies to reach out to students and insure some level of learning, especially among those without internet connectivity.