Receptor for different ligands such as phospholipids, cholesterol ester, lipoproteins, phosphatidylserine and apoptotic cells (PubMed:12016218, PubMed:12519372, PubMed:21226579). Receptor for HDL, mediating selective uptake of cholesteryl ether and HDL-dependent cholesterol efflux (PubMed:26965621). Also facilitates the flux of free and esterified cholesterol between the cell surface and apoB-containing lipoproteins and modified lipoproteins, although less efficiently than HDL. May be involved in the phagocytosis of apoptotic cells, via its phosphatidylserine binding activity (PubMed:12016218). (Microbial infection) Acts as a receptor for hepatitis C virus in hepatocytes and appears to facilitate its cell entry (PubMed:12356718, PubMed:12913001, PubMed:18000990). Binding between SCARB1 and the hepatitis C virus glycoprotein E2 is independent of the genotype of the viral isolate (PubMed:12356718). (Microbial infection) Mediates uptake of M.fortuitum, E.coli and S.aureus. (Microbial infection) Facilitates the entry of human coronavirus SARS-CoV-2 by acting as an entry cofactor through HDL binding. The C-terminal region binds to PDZK1. (Microbial infection) Interacts with hepatitis C virus E1:E2 glycoproteins. Predominantly localized to cholesterol and sphingomyelin-enriched domains within the plasma membrane, called caveolae. Widely expressed. N-glycosylated. The six cysteines of the extracellular domain are all involved in intramolecular disulfide bonds. Genetic variations in SCARB1 define the high density lipoprotein cholesterol level quantitative trait locus 6 (HDLCQ16) [MIM:610762]. May be due to a competing donor splice site. Belongs to the CD36 family.