Cladosporium spores are ubiquitous in the air and are included in the fungal contaminants that define environmental quality. This paper provides an updated review of their concentration in the Iberian Peninsula, based on data from 12 sampling stations collected using a common non-viable volumetric sampling method and the same subsequent data-treatment techniques. The database comprised 84 annual periods, covering the period 1993–2009. Mean annual total spore concentrations for each station, calculated as the sum of daily concentrations, ranged from 54 459 in Cartagena to 933 485 in Sevilla; other sampling stations recorded annual total spores between 93 052 (Porto) and 579 953 (Mérida). Analysis of annual spore-distribution patterns revealed either one or two peaks (spring and fall) depending on the location and prevailing climate of the area where the sampling stations have been placed. For all stations, average temperature was the meteorological parameter displaying the strongest positive correlation with airborne spore concentrations.