This document lays out a timeline of major changes to the Health Insurance Marketplace resulting from the Marketplace Integrity and Affordability Rule as well as H.R. 1 (formerly known as the “One Big Beautiful Bill Act). This timeline details when each provision takes effect from 2025 through 2028. It highlights shifts in eligibility, enrollment processes, premium tax credits, immigrant coverage, and verification requirements, emphasizing how these changes will affect consumers’ ability to obtain and maintain Marketplace coverage.