Medicaid Home- and Community-Based Services (HCBS) 1915(c) waivers are the most prominent funding mechanism for the long-term services and supports (LTSS) of people with intellectual and developmental disabilities (IDD). This study's aim was to conduct an in-depth national analysis of fiscal year (FY) 2021 HCBS 1915(c) waivers for people with IDD. In FY 2021, over $43.2 billion was projected for the HCBS of 861,038 people with IDD. An average of $47,315 was projected per person with IDD annually. The services that received the most funding were: residential habilitation; supports to live in one's own home; and day habilitation. HCBS is necessary so people with IDD can live and thrive in their communities.