Abstract <p>Naturally occurring radioactive materials, particularly radon gas, can accumulate in groundwater through uranium decay in bedrock formations and hydrogeological transport mechanisms, potentially exposing consumers through ingestion and inhalation pathways. We have measured the radon activity concentrations in 25 groundwater samples from Iraqi Kurdistan using Rad7 detection equipment and evaluated the associated radiological health risks. The radon concentrations ranged from 20.4 to 48.5 Bq/L, with a mean of 34.0 Bq/L. All groundwater samples exceeded the USEPA maximum contaminant level of 11.1 Bq/L, while six sample surpassed the UNSCEAR recommended limit of 40 Bq/L. All measurements remained below the WHO guideline value of 100 Bq/L. The calculated annual effective doses for adults, considering both ingestion and inhalation routes, ranged from 52.3 to 124 µSv/year with a mean of 87 µSv/year. Several samples approached or exceeded the WHO reference level of 100 µSv/year, necessitating continued surveillance and potential mitigation interventions in affected locations. Excess lifetime cancer risk values ranged from 197 × 10^–6 to 471 × 10^–6, remaining below the USEPA’s acceptable threshold of 1.0 × 10^–3. Comprehensive statistical evaluation included descriptive statistics, skewness, kurtosis, Shapiro–Wilk normality testing, and correlation analysis to examine relationships between the radon levels and physicochemical water quality parameters including pH, electrical conductivity, and total dissolved solids. These groundwater sources present elevated radon concentrations exceeding certain international safety standards, indicating measurable radiological health risks to consumers. Periodic monitoring of radon concentrations in drinking water supplies, investigation of geological source characteristics, and implementation of appropriate water treatment strategies are strongly recommended to ensure compliance with safety standards and protect public health.</p>