Abstract Background Ambulatory geriatric rehabilitation (AGR) is a multidisciplinary outpatient prevention program designed to decrease hospitalisation and dependence on nursing care in multimorbid patients ≥70 years of age. We evaluated the effectiveness of AGR compared to usual care on progression of nursing care levels, nursing home admissions, hospital admissions, incident fractures, mortality rate and total cost of care during a one-year follow-up period. Methods Analyses were based on claims data from the health insurance company AOK Nordost. Propensity Score matching was used to match 4 controls to each person receiving the AGR intervention. Results A total of 632 AGR participants and 2528 matched controls were included. The standardized mean difference of matching variables between cases and controls was small (mean: + 1.4%; range: − 4.4/3.9%). In AGR patients, the progression of nursing care levels (+ 2.2%, 95%CI: − 0.9 /5.3), nursing home admissions (+ 1.7%, 95%CI: − 0.1/3.5), hospital admissions (+ 1.1%, 95%CI: − 3.2/5.4), incident fractures (+ 11.1%, 95%CI: 7.3/15) and mortality rate (+ 1.2%, p = 0.20) showed a less favourable course compared to controls. The average total cost per AGR participant was lower than in the control group (− 353€, 95%CI: − 989€/282€), not including costs for AGR. Conclusions Analysis based on claims data showed no clinical benefit from AGR intervention regarding the investigated outcomes. The slightly worse outcomes may reflect limitations in matching based on claims data, which may have insufficiently reflected morbidity and psychosocial factors. It is possible that the intervention group had poorer health status at baseline compared to the control group. Trial registration German Clinical Trials Register DRKS00008926, registered 29.07.2015.