This paper classifies the architecture, engineering, and construction enterprises in the South Transdanubia Region, Hungary, according to the size and function of the firms. It is a primary step for later investigation about the implementation of building information modeling in small and medium-sized enterprises within the region. It introduces digital construction in the sector, includes most construction firms based in the region, and systematically gathers data. It analyzes the data to introduce a new sorting method based on the local construction market, unlike the international classification, which leans on the global perspective.