Purpose: The As Low As Reasonably Achievable (ALARA) principle aims to minimize radiation exposure for patients and staff. This study evaluates ALARA's impact on patient radiation exposure and clinical outcomes in endourological procedures. Methods: This retrospective study analyzed 755 patients undergoing endourological procedures (percutaneous nephrolithotomy (PCNL), ureteroscopy (URS), shock wave lithotripsy (SWL), and JJ insertion and replacement), divided into limited- versus strict-ALARA adherence groups. We assessed radiation exposure (dose area product (DAP) and fluoroscopy time (FT)) and clinical outcomes (operative time (OT), stone free rate (SFR), complications). Results: Significant DAP reductions were achieved with ALARA: 90.2% (PCNL), 92.9% (URS), 63.6% (SWL), 95.1% (JJ insertion), and 94.6% (JJ replacement) (all p < 0.001). FT also decreased significantly: 58.4% (PCNL), 64.7% (URS), 18.2% (SWL), 60.3% (JJ insertion), and 62.4% (JJ replacement) (all p < 0.001). In the ALARA group, median DAP values and FT were: PCNL (3440.0 mGycm2, 3 min 17 s), SWL (2620.0 mGycm2, 2 min 26 s), JJ insertion (247.0 mGycm2, 26 s), JJ replacement (199.5 mGycm2, 19 s), and URS (158.5 mGycm2, 15 s). Patient outcomes, including SFR and postoperative complications, did not differ between the ALARA and non-ALARA groups across all procedures. Operative time was shorter in the ALARA group for both PCNL (p = 0.042) and URS (p = 0.012). Conclusion: To our knowledge, this is the first multi-modality analysis linking strict ALARA adherence to exposure reduction and unchanged clinical outcomes across PCNL, URS, SWL, and stenting. Prospective, randomized trials should validate these novel results. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2025.