The purpose of this study was to compare the effectiveness of 1470- and 980-nm lasers with regard to power output, complications, recanalization rates, and treatment response. We prospectively evaluated the effectiveness of endovenous laser ablation (EVLA) in a total of 152 great and small saphenous veins from 96 patients. Lasers were randomly used based on the availability of the units. Patients were clinically evaluated for Clinical Etiologic Anatomic Pathophysiologic (CEAP) stage and examined with Doppler ultrasound. Treatment response was determined anatomically by occlusion of the vein and clinically by the change in the venous clinical severity score (VCSS). Seventy-eight of the saphenous veins underwent EVLA with a 980-nm laser and 74 underwent EVLA with a 1470-nm laser. Treatment response was (68) 87.2 % in the 980-nm group and (74) 100 % in the 1470-nm group (p = 0.004). The median VCSS decreased from 4 to 2 in the 980-nm group (p < 0.001) and from 8 to 2 (p < 0.001) in the 1470-nm group. At 1-year follow-up, seven veins treated with 980 nm and two veins treated with 1470 nm were recanalized (p = 0.16); the average linear endovenous energy density (LEED) was 83.9 (r, 55-100) J/cm and 58.5 (r, 45-115) J/cm, respectively (p < 0.001). Postoperative minor complications occurred in 23 (29.4 %) limbs in the 980-nm group and in 19 (25.6 %) limbs of the 1470-nm group (p = 0.73). EVLA with the 1470-nm laser have less energy deposition for occlusion and better treatment response.