An employer-sponsored program designed to encourage healthy behaviors, manage chronic conditions, or reduce healthcare costs - generally regulated under HIPAA wellness rules and (when financial incentives are involved) Section 125.
Many Section 125 indemnity products in the market call themselves 'wellness plans.' The EHP SIMERP also has wellness components, but the structural label that matters for compliance is whether the plan reimburses incurred medical expenses (SIMERP) or pays fixed event-based amounts (indemnity).
Definitions only do so much. A live walkthrough of how all of this connects in your business takes about half an hour.