Renal involvement in β-thalassemia minor (β-TMin) has been described mainly in case reports and small observational studies, and its clinical significance remains incompletely characterized. Using real-world data from routinely collected electronic medical records, we performed a retrospective cohort study including 1516 adult patients with β-TMin insured by Clalit Healthcare Services to explore renal abnormalities identified during routine clinical care. Urine testing for hematuria, microalbuminuria, and proteinuria was not performed systematically but was ordered at clinicians’ discretion, resulting in evaluation of a clinically selected subset of patients. Among those tested, hematuria, microalbuminuria, and proteinuria were commonly documented, often in the absence of hypertension, diabetes mellitus, congestive heart failure, or impaired kidney function, consistent with largely subclinical renal involvement. Patients who underwent urine testing were older and had more comorbidities than untested patients, indicating potential selection bias. Correlation analyses showed weak associations between hematological and renal parameters, while ferritin levels correlated modestly with selected proteinuria measures. Due to the retrospective design and non-systematic urine assessment, population-level prevalence and clinical impact cannot be determined. Therefore, prospective studies with standardized renal evaluations are needed to better characterize the frequency, mechanisms, and clinical relevance of renal abnormalities in β-TMin.