HbA1c test – monitoring type 2 diabetes

If you have diabetes, your GP or diabetes clinic team will use your HbA1c to assess your blood glucose control and check how well your lifestyle measures such as diet and exercise, together with your diabetes medicines, are working.

The overall aim of  treatment with diabetes medicines is to help reduce glycated haemoglobin (HbA1c) levels and the risk of complications. HbA1c is also used to diagnose diabetes and pre-diabetes. Read more about the HbA1c test for diagnosing diabetes and pre-diabetes. 

On this page, you can find the following information:

What are healthy HbA1c levels for people with diabetes?

An HbA1c level of 50 mmol/mol or greater, usually indicates that you have type 2 diabetes and you will be prescribed medicines to control your blood glucose. You should check your HbA1c levels every 3–6 months, to see how well your medicines are working.
(Health Navigator Charitable Trust and Synergy Film, NZ, 2014)

The target HbA1c for most people with type 2 diabetes is < 53 millimoles per mole (mmol/mol). This may vary from person to person, depending on your age, your other health conditions and your risk of hypoglycaemia (low blood glucose). Ask your doctor or nurse what your target HbA1c is.

Generally, the higher your HbA1c is, the greater your risk of complications from diabetes. The following provides a general guide:

Image: Auckland Hospital, NZ

How often should I get my HbA1c tested?

You should get your HbA1c tested every 3 to 6 months. HbA1c is a measure of the amount of glucose in your blood over the previous 3 months and it is used to assess your overall blood glucose control. This is to check how well your lifestyle measures such as diet and exercise, together with your diabetes medicines, are working. 

Do I need to check both my blood glucose (sugar) and HbA1c levels?

You should check your HbA1c every 3–6 months. But, regular testing of blood glucose levels at home using a blood glucose test meter (also called the finger-prick test) is generally not needed unless you are:

  • starting or already taking glipizide, gliclazide or glibenclamide – this is because the risk of hypoglcaemia (low blood glucose) is higher with these medicines
  • starting or already taking insulin
  • at risk of frequent episodes of low blood glucose (hypoglycaemia)
  • planning a pregnancy or are pregnant.

Read more about home blood glucose testing for type 2 diabetes.


  1. Optimising pharmacological management of HbA1c levels in patients with type 2 diabetes – from metformin to insulin BPAC, NZ, 2019

Reviewed by

Dr Jeremy Tuohy is an Obstetrician and Gynaecologist with a special interest in Maternal and Fetal Medicine. Jeremy has been a lecturer at the University of Otago, Clinical leader of Ultrasound and Maternal and Fetal Medicine at Capital and Coast DHB, and has practiced as a private obstetrician. He is currently completing his PhD in Obstetric Medicine at the Liggins Institute, University of Auckland.
Credits: Health Navigator Editorial Team. Reviewed By: Dr Jeremy Tuohy, Obstetrician, Gynaecologist, Capital and Coast DHB and researcher, University of Auckland