The COVID-19 pandemic has affected humankind worldwide, slowing down and even reversing the progress made in achieving Sustainable Development Goals (SDGs). It has negatively impacted most SDGs but with positive impacts on a few. We discuss some initial impacts observed and explores potential impacts on the achievement of SDGs for Nepal. The study followed a knowledge co-creation process with experts from various professional backgrounds, involving five steps: online survey, online workshop, assessment of expert’s opinions, review and validation, and revision and synthesis. The pandemic has restricting impacts on the progress of most SDGs. However, it has also opened a window of opportunity for sustainable transformation. Many of the negative impacts may subside in the medium and long terms. The negative impacts on SDGs resulted from factors linked to the pandemic or the measures taken to control it. The key five impending factors are lockdowns, underemployment and unemployment, closure of institutions and facilities, diluted focus and funds for non-COVID-19 issues, and anticipated reduced support from development partners. The generated transformative opportunities are lessons learned for planning and actions, socio-economic recovery plan, use of information and communication technologies and impetus to the digital economy, reverse migration and ‘brain gain,’ and local governments’ exercising authorities. For sustainable transformation, the window to grasp these opportunities is short-lived and will get narrow over time, i.e., before rebounds occur following the past trajectories.