Purpose <p>The objective was to assess whether the size of the supraspinatus tendon retraction following a degenerative full-thickness rotator cuff tear influenced the functional outcome after arthroscopic direct repair.</p> Methods <p>A prospective comparative cohort study of 65 patients underwent arthroscopic rotator cuff repair with a follow-up of 24 months. The mean age was 60.0 years (SD, 9.2). According to the supraspinatus tendon retraction, patients were included into the shorter retraction group (≤ 20&#xa0;mm; <i>n</i> = 32) and longer retraction group (&gt; 20&#xa0;mm; <i>n</i> = 33). Clinical outcomes were assessed with the Constant-Murley score and visual analogue scale for pain. Radiological evaluation included magnetic resonance imaging (MRI).</p> Results <p>Postoperatively, both groups significantly improved functional and pain outcomes, with no significant differences at the final follow-up (<i>p</i> = 0.671). The mean time interval between the onset of patient-reported symptoms and surgery was not significantly correlated with the retraction size (<i>r</i> = 0.12, <i>p</i> = 0.066). The multivariate analysis did not show significant predictors of satisfactory functional outcome, especially the tendon retraction size (OR 1.0; 95% CI 0.9–1.1; <i>p</i> = 0.728).</p> Conclusion <p>In degenerative tears, the size of the supraspinatus tendon retraction was not correlated with the duration of the symptoms. The tendon retraction of up to 4&#xa0;cm did not influence the functional outcome at 24 postoperative months, regardless of the arthroscopic repair technique of one or two rows.</p>