Among the most significant sources of microplastics (MPs) for humans is indoor dust. However, very few researchers have studied the properties and abundance of MPs that existed in dust from different indoor environments. The current study investigated microplastic fallout in 90 locations (5 kindergartens, 6 mosques, 5 schools, 10 shops, 5 cafeterias, 6 hospitals, 25 dormitories, 7 barber salons, 6 offices, 5 scientific laboratories, 5 pharmacies, and 5 medical clinics) during six months. Among the ninety sampling sites, the most significant average of MPs was actually found in the kindergartens (4.743x103 ± 427 MP/m2 /d), in contrast, the lowest abundance was in the medical clinics (302 x102 ±62 MP/m2 /d). The majority of indoor dust samples contained MPs in the form of fibers. The dominant colour of dust samples was transparent, followed by black, red, blue, green, and yellow. A total of six types of polymers were identified, including polystyrene (PS, 39%), polyethylene terephthalate (PET, 20%), polypropylene (PP, 17%), polyethylene (PE, 13), polyamide (PA, 7%) and polyvinyl chloride (PVC, 3%). PS, PET, and PP represent most of the MPs polymer types discovered in indoor dust samples from various locations. These polymers are frequently used in fabrics, furniture, carpets, packaging, and synthetic fibers. Statistical analysis was performed on the results using Excel 2019. The results showed that there were statistically significant differences in each site with the other sites, except between (schools and mosques), (pharmacies, and medical clinics). The similarity between these sites in terms of people’s activity or in terms of furniture, the lack of carpets and curtains could explain the insignificant difference.