This study investigates rebar corrosion in geopolymer concrete with three water-to-binder ratios (0.45, 0.5, and 0.55) and two binder contents: ground granulated blast furnace slag (GGBS) alone or equal fractions of fly ash (FA) and GGBS. The corrosion performance of embedded rebar in geopolymer concrete was tested in wet (7 days) and dry (14 days) cycles with 3.5 %, 5 %, and 7.5 % NaCl. The cast cylindrical specimens were tested for half-cell potential and corrosion current density using linear polarization resistance (LPR) after 28 days ambient curing at 1, 7, and 150 days per ASTM G109 for each exposure condition. The cube specimen was tested for compressive strength at 7 and 28 days of curing. Binders, water-to-binder ratio, testing age, and NaCl exposure percentages affect geopolymer concrete rebar corrosion. Due to decreased pore size and greater C-A-S-H and N-A-S-H gel formation, GGBS-based geopolymer concrete has a higher compressive strength than fly ash and GGBS. A blend of fly ash and GGBS-based geopolymer concrete with a waterto-binder ratio of 0.55 had a higher corrosion risk based on the investigation.