Health coaching is a common approach for promoting lifestyle changes, but little is known about the effectiveness of different delivery methods. The purpose of this study was to evaluate the effectiveness of in-person versus online health coaching when used as part of a facilitated behavior change program. To increase translatability, the study used a naturalistic design that enabled participants to self-select the coaching delivery method (Group) as well as the target behavior (diet, physical activity, or weight management). Regardless of group, participants were provided with a behavior-based monitoring device and guided to use it by the health coach. A sample of 92 adults participated and 86 completed pre–post evaluations to assess behavior change strategies and posttest outcome measurements for their specific goal. Two-way (Group × Time) analyses of variance were used to evaluate changes in behavioral strategies. Intent-to-treat regression analyses were used to compare postintervention outcomes for groups. The in-person group had significantly higher Healthy Eating Index scores than the online group (p < .05), but nonsignificant group differences were observed for those targeting physical activity or weight change (p > .05). The results support the use of health coaching for promoting behavior change and suggest that online coaching may be equally effective as in-person methods.