Preventative care is covered at no cost by health insurance plans because of the Affordable Care Act (ACA). The ACA requires health insurance plans to cover certain preventive services without any cost-sharing, such as copays, coinsurance, or deductibles. This includes services such as annual check-ups, screenings for various health conditions, and immunizations. The goal of this requirement is to encourage people to receive preventive care, which can help detect health problems early, prevent the development of chronic diseases, and ultimately reduce healthcare costs.