Purpose To evaluate the effectiveness of a workplace integrated care intervention on at-work productivity loss in workers with rheumatoid arthritis (RA) compared to usual care. Methods In this randomized controlled trial, 150 workers with RA were randomized into either the intervention or control group. The intervention group received an integrated care and participatory workplace intervention. Outcome measures were the Work Limitations Questionnaire, Work Instability Scale for RA, pain, fatigue and quality of life (RAND 36). Participants filled out a questionnaire at baseline, and after 6 and 12 months. We performed linear mixed models to analyse the outcomes. Results Participants were on average 50 years of age, and mostly female. After 12 months, no significant intervention effect was found on at-work productivity loss. We also found no significant intervention effects on any of the secondary outcomes. Conclusions We did not find evidence for the effectiveness of our workplace integrated care intervention after 12 months of follow up. Future studies should focus on investigating the intervention in groups of workers with severe limitations in work functioning, and an unstable work situation.