A1C
A1C may refer to:

Biology and chemistry
Glycated hemoglobin (hemoglobin A1c or  HbA1c), a surrogate marker for blood glucose levels
A1C recepter, the alpha-1C adrenergic receptor

Transportation and vehicles
 Rivian A1C, a prototype CUV, predecessor of the Rivian R1S
 MV (A1C) William H. Pitsenbarger, U.S. maritime sealift command container ship
 NASA A1C spacesuit, an Apollo variant of the Gemini spacesuit

Other uses
Airman First Class, the third enlisted rank in the United States Air Force
A1C, a postal code occurring in Downtown St. John's, Newfoundland Island, Newfoundland and Labrador, Canada

See also

 
 AIC (disambiguation)
 ALC (disambiguation)