This study aimed to compare patient outcomes and residual complains after hip arthroscopy (HAS) and total hip arthroplasty (THA) to improve patient counseling. It includes 140 hips/129 HAS-patients and 77 hips/62 THA-patients aged 40 to 55 years with a BMI under 30. All patients underwent primary HAS or primary THA in our hospital from 2007 until 2014. Exclusion criteria were a history of prior hip surgery or suffering sequels of childhood's hip disease, systemic inflammatory disease or avascular hip osteonecrosis. Outcome measures were WOMAC, subjective hip value, residual complains, the need of infiltrations and the complication and conversion rate. Patient data and scores were collected pre-operative, after one year and at the last follow-up. Scores indicated significant patient benefits in both groups (p < 0.0001). Variability of outcome was significantly higher and less predictable in the HAS group (HAS: 1.9 vs. THA: 0.9). While THA showed significant improvement mainly after one year, HAS showed significant improvements after one year and the latest follow-up. Residual complains were more frequent after HAS (p = 0.026). Groin pain was the main complain after HAS, limping and disturbing leg length discrepancy after THA. THA more predictably improves patient's outcome with shorter recovery time. Limping and leg length discrepancy are predominant after THA.