OBJECTIVES: To estimate the health and economic value of participation in digital lifestyle intervention program for people with prediabetes  METHODS: The study investigated ‘Prevent’ program which is modeled after CDC’s Diabetes Prevention Program. The core phase of this digital program consisted of 16 weekly lessons, followed by periodic follow-up to reinforce lesson content and provide encouragement. The analysis sample included 2,371 Prevent participants who were overweight or obese and have prediabetes. Participants’ weight at or before 26 weeks was studied to calculate weight change. A Markov-based microsimulation model simulated onset of obesity and diabetes comorbidities annually over 10 years among participants under two scenarios (1) weight loss and A1c improvements achieved through Prevent, and (2) natural history of disease in the absence of Prevent. A second population that met USPSTF’s recommendation for intensive behavioral counselling was also evaluated following the same process to estimate the benefits of ‘Prevent’ in different populations. RESULTS: Participants with prediabetes experienced average weight loss of 5.13%. Prevent was associated with a 28% reduction in diabetes onset over 3 years and 30% over 5 years. Cumulative over 3 and 5 years, the present value of reduced medical expenditures averaged $1,310 and $2,870, respectively. Comparing medical savings to program costs, the break-even point was two years. The simulated return on investment (ROI) was $860 after 3 years, $2,420 after 5 years, and $8,770 after 10 years. In the USPSTF population, the model projected reduction in disease onset similar to that in the prediabetes population. The ROI was $950, $2,370 and $7,500, for 3, 5, and 10 years, respectively.  CONCLUSIONS: Intensive lifestyle intervention is recommended by the U.S. Preventive Services Task Force as the first-line treatment for prediabetes, and internet-based programs like Prevent appear to provide both substantial health benefits to participants and high return on investment.