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The influence of grazing on soil seed bank (SSB) characteristics determines the management of rangelands in different climates. Here we studied the responses of SSBs to livestock grazing in three regions with different climates – arid, semiarid and subhumid – in northern Iran. In each region 30 pairwise SSB samples were collected on 1 m2 plots, 15 in intensely grazed areas and 15 in ungrazed areas. The total SSB densities, their diversity and species richness and the densities of functional groups were compared between the grazed and ungrazed plots and between the climatic regions. Both climate and grazing as well as their interaction affected SSB characteristics. Although the results of the non-metric multidimensional scaling (NMDS) showed noticeable differences in SSB species composition between grazed and ungrazed plots in all three regions, the magnitude of the grazing effect on the SSB was different between climatic regions. In total, 119 species germinated from the soil samples: 33 species in semiarid, 39 species in arid and 61 species in subhumid samples. The highest total SSB density, diversity (Shannon index) and richness were found in subhumid climate with an average of 138.90 seeds/m2, H = 2.27 and 17.83 species/sample, respectively. In ungrazed areas the average SSB density was 26.60 seeds/m2, 46.06 seeds/m2 and 195.90 seeds/m2 in arid, semiarid and subhumid climate, respectively. In grazed areas the corresponding figures were 12.40 seeds/m2, 7.00 seeds/m2 and 110.40 seeds/m2. Averages of SSB diversity in ungrazed areas were 1.24, 1.60 and 2.42 in arid, semiarid and subhumid climates, respectively, as compared to 1.27, 0.97 and 2.20 in grazed areas. The averages SSB richness in ungrazed areas were 5.21 species/sample, 7.54 species/sample and 21.25 species/sample in arid, semiarid and subhumid climate, respectively, whereas in grazed areas 4.00 species/sample, 2.86 species/sample and 16.15 species/sample were found on average. Overall, intensive grazing was linked to lower SSB characteristics in all three climatic regions, but the size of the effect differed between the climatic regions. Thus, we concluded that the impact of grazing on SSB density, diversity and richness is climate-dependent. Hence, the climatic conditions have to be considered when evaluating the effects of grazing on soil seed banks. • Soil seed bank (SSB) is an important part of plant communities. • We studied the responses of SSB to grazing in three regions with different climates. • Intensive grazing suppressed SSBs, consistently across all climatic regions. • The magnitude of impact of grazing on SSB characteristics is climate-independent. [ABSTRACT FROM AUTHOR]