Do you have to fast for hemoglobin a1c test?

No: For hba1c alone, no fasting is required, but it is often done with other tests, like cholesterol or blood sugar, for which fasting is indicated.

Hgb-a-1-c: Is used to monitor diabetic treatment. I get mine 3 -4 times per year.You do not have to fast for it, because it shows how well your blood levels have been controlled for months. The fbs, and 2 hr postprandial, and 4pm are done both to diagnose and discern management...These are done after an overnight fast.

Short answer: The test measures indirectly measures glucose control over the preceding 6-8 weeks. It does not measure sugar directly; therefore i would believe it not to be necessary to fast prior to the test. However, the best way to answer this question is to call the lab where you go to have the blood drawn and ask them directly whether you need to fast for the test.