How effective are behavioral interventions to increase the take‐up of social benefits? A systematic review of field experiments

Non‐take‐up of social benefits is a significant policy issue caused by factors such as lack of awareness, compliance costs, and stigma. While public information campaigns, default options, and in‐person assistance are increasingly used, their effectiveness remains poorly understood. This study provides a systematic review of field experiments evaluating nudges and simple behavioral interventions on program take‐up. We analyzed 93 interventions from 35 studies published over nearly 20 years, predominantly focusing on major U.S. programs. We compared study characteristics, including sample and intervention types, and assessed study quality. Due to high heterogeneity, we did not conduct a meta‐analysis but used forest plots and thematic summaries instead. Most studies reported a positive impact on program take‐up, but not on program application. Two types of interventions were notable for their impact on program application and take‐up: 1) providing and framing information; and 2) providing assistance. We discuss the limitations of this review, including the cost and safety of nudges and the implications of focusing on field experiments. We conclude that further research is needed on simpler interventions outside the U.S., as well as on compliance and psychological costs. Additionally, improving the quality and transparency of field experiments is essential.