Provided are select imidazo[1,2-f][1,2,4] triazinyl nucleosides, nucleoside phosphates and prodrugs thereof, wherein the 2' position of the nucleoside sugar is substituted with halogen and carbon substituents. The compounds, compositions, and methods provided are useful for the treatment of Flaviviridae virus infections, particularly hepatitis C infections caused by both wild type and mutant strains of HCV. Formula (I)
