Multiple Employer Welfare Arrangement Act or the MEWA Act This bill provides statutory authority for the treatment of association health plans (AHPs) as single, large employer health plans for purposes of the Employee Retirement Income Security Act (ERISA). Under AHPs, groups of individuals or small employers join together to purchase health insurance coverage. AHPs were historically subject to the market requirements for individual and small group health plans. In 2018, the Department of Labor issued regulations that allowed an AHP to be considered a single, large employer under ERISA if certain conditions are met. The regulations have been subject to litigation, which is still ongoing. The bill provides that a group of employers is treated as a single, large employer for the purpose of establishing an AHP if the group, among other listed criteria (1) has been in existence for at least two years and was formed for a purpose other than offering health insurance, (2) meets any criteria set by Labor in a prior advisory opinion, or (3) meets any other criteria set by Labor through regulations. Additionally, the bill establishes rules for AHPs to set premium rates and prohibits AHPs from discriminating in coverage based on health status-related factors or denying coverage based on preexisting conditions.