All Marketplace plans must cover treatment for pre-existing medical conditions. Once you are enrolled in an ACA health plan, no Marketplace insurer can reject you, refuse to pay for essential health benefits, or charge you more for any condition you had before your effective date. Also, the insurer cannot raise your rates, deny you coverage, or cancel your policy based only on your health. Insurers can only adjust rates at renewal time for all enrollees and not just based on your individual health.