Fast 100 – Houston Business Journal 2020 represents Houston’s fastest-growing private companies based on revenue growth from 2017 to 2019. Southland Mechanical was ranked 57 of the top 100 companies.

Information was obtained from firm representatives. Information on The List was supplied by individual companies through questionnaires and could not be independently verified by the Houston Business Journal. Only those that responded to HBJ inquiries were listed. In case of ties, companies are listed alphabetically.