Background: Mechanical thrombectomy in late-presenting stroke patients with a limited infarct core on CTP/DWI is highly effective. We aimed to evaluate the degree of disability at discharge as an indicator for functional impairment at one and three months after mechanical thrombectomy compared to medical management in these patients. Methods: This study concerns a post-hoc analysis of the DAWN-trial population. Patients presenting 6-24h after symptom onset of an emergent large vessel occlusion with mismatch between symptom severity and infarct size on CTP/DWI, were randomized for medical management versus mechanical thrombectomy. We assessed the change in modified Rankin score (mRS) from discharge up to three months post-stroke for DAWN-patients treated with mechanical thrombectomy compared to those randomized to medical management. Kendall’s tau test was used to evaluate the correlation between the mRS at discharge, at 30 days, and at 90 days. Mixed models were used to explore the potential difference between treatment arms in the change of utility weighted mRS over time. Results: Ninety-eight of 107 patients treated with mechanical thrombectomy and 89/99 controls survived at discharge and were included in the analysis. We found a strong correlation between the mRS at discharge, at 30 days, and at 90 days for both treatment arms with a tau varying from 0.52 to 0.72 for mechanical thrombectomy and 0.56 to 0.71 for medical management. All correlation coefficients were statistically significant (p < 0.0001). The utility weighted mRS after mechanical thrombectomy was consistently superior to medical management (p < 0.0001). Although there was a trend towards a stronger dispersion of the utility weighted mRS over time after mechanical thrombectomy, there was no statistically significant interaction effect between time and treatment arm (p 0.44). Conclusion: The treatment effect of mechanical thrombectomy occurs early and further improvement over time is similar to that of medical management. The mRS at discharge is a robust indicator for functional status at one and three months post stroke and may therefore be used as an alternative measure for clinical outcome.