Solar energy is an abundant and renewable source of energy that can help to mitigate challenges such as air pollution and global climate change. Several models have been developed to estimate solar radiation from geostationary satellite images, however each of these models are instrument specific and require modifications to be used with images from other instruments. A large portion of Iran is geographically located in an arid region with a great potential for solar energy applications. Previous studies to investigate the spatial and temporal variation of solar radiation over Iran has relied on measurements from radiometric stations. This study leverages the satellite measurements to evaluate the spatial and seasonal variation of solar radiation over the county. The study uses the Heliosat-II method to retrieve solar radiation from Meteosat-5 images. The mean annual bias and RMSE of the retrievals when compared with measurements ranges between 1.85%-8.3% and 9.9%-14.0%, respectively. The country can be divided into six zones based on mean annual incoming radiation: i) the coastal regions of the Caspian Sea and the mountainous areas of the Northwest, with incoming radiation ranging from 3200 to 4520 Wh•m −2 ; ii) the Northwest region, with incoming radiation between 4520 and 4960 Wh•m −2 ; iii) the region extending from the Southwest and West to the capital, Tehran, and towards the Northeast, with incoming radiation between 4960 and 5400 Wh•m −2 ; iv) the central region, with incoming radiation ranging from 5400 to 5800 Wh•m −2 ; v) the eastern part of the country and some segmented regions in the central part, with incoming radiation between 5800 and 6000 Wh•m −2 ; and vi) the Southeast, with incoming radiation ranging from 6000 to 6800 Wh•m −2 .