New faunistic and taxonomic data are provided for 18 families of Iranian spiders. Eleven species from eastern Iran are described as new to science: Cheiracanthium minusculum Zamani & Marusik, sp. nov. (♂; Sistan & Baluchistan), C. monstrum Zamani & Marusik, sp. nov. (♂♀; South Khorasan), C. sistani Zamani & Marusik, sp. nov. (♀; Sistan & Baluchistan) [Cheiracanthiidae], Cithaeron persicus Zamani & Marusik, sp. nov. (♀; Sistan & Baluchistan) [Cithaeronidae], Archaeodictyna longichela Zamani & Marusik, sp. nov. (♂♀; Sistan & Baluchistan), Devade miniatura Zamani & Marusik, sp. nov. (♀; Razavi Khorasan) [Dictynidae], Talanites sakastanicus Zamani & Marusik, sp. nov. (♀; Sistan & Baluchistan) [Gnaphosidae], Philodromus parvulus Zamani & Marusik, sp. nov. (♀; Sistan & Baluchistan), Rhysodromus tikhmenevi Zamani & Marusik, sp. nov. (♂; Sistan & Baluchistan) [Philodromidae], Steatoda pallens Zamani & Marusik, sp. nov. (♀; Sistan & Baluchistan) [Theridiidae] and Bassaniodes drangianus Zamani & Marusik, sp. nov. (♂♀; Sistan & Baluchistan) [Thomisidae]. The females of Trichothyse hamipalpis (Kroneberg, 1875) [Gnaphosidae] and Rhysodromus medes Zamani & Marusik, 2021 are described for the first time. A new combination, Rhysodromus latrophagus (Levy, 1999) comb. nov. (ex. Philodromus), is proposed. The subfamily Coelotinae, the genus Brignoliolus Ovtchinnikov, 1999 [both Agelenidae] and seven species are reported from Iran for the first time, and the Iranian record of Steatoda nobilis (Thorell, 1875) is rejected. Additionally, 52 new provincial records are provided for 47 species.