Financial incentives can powerfully influence behavior, yet their effects often fade once payments stop. We investigate whether long-term incentive designs that leverage performance history can produce lasting habits. In a 51-week field experiment (N = 523), participants received personalized daily walking goals tracked via wearables and were randomly assigned to five conditions: no incentive, fixed-value rewards or penalties, or “streak-based” incentives that linked payoffs to consecutive successes or lapses. During the 36-week intervention, all incentive conditions increased step counts by 12–17% versus control. Remarkably, gains persisted for 12 weeks post-intervention with minimal decay in all incentive conditions. Importantly, gain-streak incentives reinforced daily momentum, while loss-streak incentives reduced lapses. The results suggest that personalized daily goals, when coupled with longer incentive periods and dynamic incentive designs, can foster durable and distinct walking habits, offering a scalable framework for behavior change.