Throughout Earth history a small number of global catastrophic events leading to biotic crises have caused mass extinctions. Here, using a technique that combines taxonomic and numerical data, we consider the effects of the Cenomanian–Turonian and Cretaceous–Tertiary mass extinctions on the terrestrial spider fauna in the light of new fossil data. We provide the first evidence that spiders suffered no decline at the family level during these mass extinction events. On the contrary, we show that they increased in relative numbers through the Cretaceous and beyond the Cretaceous–Tertiary extinction event.