The COVID-19 pandemic has left significant consequences at every level of education, including adult education. In order to adapt to the restriction caused by the pandemic, adult education institutions all around the world were forced to transform the way how the educational process was being organized. By introducing various web-related technologies, the physical place of teaching and learning processes has become a less significant factor, thereby, potentially, contributing to the inclusiveness of education and, as a result, to sustainable development. The paper aims to analyze how the recent transformation of adult education caused by the pandemic between 2020 and 2022 contributed to the sustainable development of Latvia. To achieve the aim, the following research methods are used: a scientific literature review to investigate the concepts of sustainable development and online adult education as well as their potential correlation, a survey of adult education institutions in Latvia, as well as statistical data analysis of adult education indicators. The main findings of the article: during the pandemic when the in-person teaching process was restricted, the Latvian adult education sector experienced unprecedented digital transformation. The transformation positively contributed to the improvement of not only the digital skills of teachers and learners but also to the sustainable development of Latvia by facilitating access to potential learners living in rural areas and regions.