The paper ‘Mass function of dormant black holes and the evolution of active galactic nuclei’ was published in Mon. Not. R. Astron. Soc. 307, 637–644 (1999). Owing to a typing error which was overlooked when the paper was revised for publication, in Section 2 (and only in this section) the ‘h2 ’ should be removed from formulae giving the mass density ρMDO.