Biportal endoscopy spine surgery is an endoscopic procedure that uses 2 portals, 1 for the endoscope and 1 for the instruments. It provides an excellent and very versatile field of view, with the advantage of another portal to approach the most common degenerative lumbar pathologies. We evaluated a retrospective series of patients who underwent biportal endoscopy with ≥1 year of follow-up. Relevant epidemiological and clinical data, such as the Oswestry disability index and visual analog scale for pain, were also considered. Complications and the effects of the learning curve are also discussed. We included 163 patients treated within a 5-year period with ≥1 year of follow-up available. The main pathologies were disc herniation (53.4%), foraminal stenosis (19%), and central canal stenosis (16.6%). The outcomes regarding disability and pain scores after surgery were very good, with a redistribution of the patient sample to the mild categories of disability. Inferential analysis showed relative and absolute improvements for both disc herniation and canal stenosis in terms of the Oswestry disability index and visual analog scale for pain, especially for disc herniation. The incidence of complications was approximately 7%. The most common approach was interlaminar (89%), and the most common pathology was disc herniation (54.9%). The duration of surgery overall and for the different stages had improved at the end of the learning curve with a reduction of almost 58 minutes. Biportal endoscopy is a minimally invasive procedure that is safe and effective, with a low rate of complications. It has a reproducible learning curve and provides very good outcomes regarding functionality and pain scores.