His parents, wine merchant Herman Fabritius (1667-1729) and Elisabeth Marie Abbestée (1677-1752), were immigrants from Germany and belonged to the city's German Reformed congregation.

Like the other major merchants of his time, Michael Fabritius had close ties to the state, providing it with loans and participating in the equipping of ships in connection with expeditions to overseas destinations.

Michael Fabritius married Anna Maria Köster (17 November 1705 in Frankfurt – 18 March 1775) on 30 May 1726 in Mühlheim.

Their two sons, Michael and Conrad Alexander, were ennobled by letters patent on 4 May 1776 under the name Fabritius de Tengnagel.

Their younger daughter, Charlotte, married shipowner, merchant and textile manufacturer Peter van Hemert.