The purpose of this study is to assess the level of sustainability practices adoption in small-and-medium-sized accommodation and its possible impact on competitive advantage. An operational model is developed and tested with relevant hypotheses based on the primary data collected from accommodation's top-level management. The study results show that the effect of the determinants of technology-organization-environment on sustainability practices adoption is positively significant. The impact of sustainability practices on competitive advantage is positively significant. Likewise, the impact of technology-organizationenvironment determinants on sustainability practices adoption is positively significant. Furthermore, sustainability practices adoption mediates the relationship between technology-organization-environment and competitive advantage. The findings in this study will assist the owners and managers of SMEs tourist accommodation to enhance their sustainability practices adoption. Likewise, this study links the gap of current literature on sustainability practices adoption assessment in another developing country. Thus, the researcher used this concept in the Philippines setting, particularly in the selected Regions in the Philippines.