Purpose: This study examined whether job and personal resources could buffer the negative effects of technostrain and information and communication technology (ICT) availability demands on employee well-being. Design/methodology/approach: The data were collected among Finnish comprehensive school teachers (n = 323) between December 2020 and February 2021 through an online questionnaire. Hierarchical multiple regression analyses were employed to analyse the main and moderating effects. Findings: The results indicated that technostrain was positively associated with burnout and negatively associated with work engagement. These associations were stronger than those of ICT availability demands. The moderated regression analyses revealed that psychological detachment buffered the negative effects of technostrain on cynicism and a sense of inadequacy. School support acted as a moderator by buffering the negative impact of technostrain on emotional exhaustion and cynicism. Furthermore, school support was found to be an important job resource in terms of boosting work engagement when ICT availability demands were high. Originality/value: This study provides insights into the role of resources in buffering possible burdening effects of technology on teacher well-being when adopting online teaching in the context of the COVID-19 pandemic.