The main contribution to population exposure is due to radon and thoron progenies and not radon itself. The aim of this study was therefore to estimate annual effective dose using the results of Direct Radon and Thoron Progeny Sensors were exposed in 69 selected schools and 319 dwellings in several regions of Balkans: in Serbia: regions of Sokobanja and Kosovo and Metohija, Republic of Macedonia, Republic of Srpska and Slovenia. Obtained average total effective doses are in the range from 0.22 mSv a−1 (schools in Republic of Srpska) to 2.5 mSv a−1 (dwellings in Kosovo) and are below the reference level of 10 mSv a–1 recommended by International Commission on Radiological Protection.