Data on the size of the beetle fauna of North America north of Mexico are summarized from the newly published volumes of American Beetles. As currently recorded, this fauna contains 25,160 species in 3,526 genera and 129 families. Five families together contain over 50% of the species, 13 families together more than 75%, and 29 together over 90%. Sixteen families that have been fully revised or reviewed showed an average increase in species diversity of 21% since 1963 (range −20% to 116%). The total number of species reported from North America is expected to continue to increase to nearly 28,000 species, as reports of known undescribed species currently number in the several hundreds.