Changes to HbA1c Diagnostic Criteria

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Effective 1 July 2026, the national diagnostic thresholds for HbA1c are changing as follows:

• No diabetes: HbA1c < 42 mmol/mol.
• Prediabetes: HbA1c 42 – 47 mmol/mol (previously 41 – 49 mmol/mol)
• Diabetes: HbA1c ≥ 48 mmol/mol (lowered from the current ≥ 50 mmol/mol) No confirmatory test now required if HbA1c ≥ 53 mmol/mol
• Confirmatory test required as soon as practical if HbA1c 48 – 52 mmol/mol g. repeat HbA1c, fasting glucose or random glucose (if symptomatic)

Review of those affected by the changes can wait until clinically due as part of routine care (e.g. annual follow up of prediabetes or post gestational diabetes, or when CVD risk assessment due etc) but may be expedited if clinical concerns. If ready, providers can apply the new criteria now on historical lab results where feasible e.g. if HbA1c 48 – 49 mmol/mol in the past 6 – 12 months. There is no change to the blood glucose diagnostic criteria for diabetes.

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What does this mean?

So from 1 July 2026, the way diabetes and prediabetes are defined in Aotearoa New Zealand is changing.

You might start to hear about these changes from your doctor, nurse, or even see different wording in your lab results before then. This can feel confusing — especially if your numbers haven’t changed, but the language around them has.

Let’s walk through what’s happening, and what it means for you.

A small shift in numbers, a wider shift in meaning

The HbA1c thresholds (the numbers used to describe blood glucose levels over time) are being updated.

• The threshold for diabetes is being lowered slightly
• The range for prediabetes is becoming narrower

This means that some people who were previously told they had prediabetes may now be told they have diabetes — even if their HbA1c result is exactly the same.

Your body hasn’t suddenly changed!

If your HbA1c result hasn’t changed, then your body hasn’t suddenly changed either. What has changed is how the health system is choosing to name and respond to risk.

The line in the sand has moved — not you.

Earlier recognition, earlier support

The intention behind these changes is to:

• Recognise risk earlier
• Offer support sooner
• Reduce long-term complications

For some people — especially those diagnosed at a younger age — earlier support can make a meaningful difference over time.

Noticing the change before it officially arrives

Over the next few months, you might notice:

• Different wording in your lab reports
• A change in how your results are described by your healthcare team
• Conversations about diabetes happening earlier than before

This may happen before 1 July as systems and services begin to transition.

Care that still centres you

For many people, nothing will change straight away.

• The same healthy living support still applies
• The same medications (like metformin) are used when needed
• Your care plan is still based on you, not just a number

What may change is the timing of conversations and support.

Making sense of the feelings that can come with new words

For some people, being told they now have “diabetes” instead of “prediabetes” can be unexpected and you might feel confused, worried, or frustrated.

But my number hasn’t changed!

All of these reactions are valid, and this is where language matters. A label is a tool for guiding care — it is not a judgment, and it does not define you.

A more gentle way to see the change

You might find it helpful to think about this shift as:

• Earlier awareness, not “worse health”
• More opportunity, not “something has gone wrong”
• Support being offered sooner, not “a line being crossed”

If you’re unsure about what your results mean for you:

• Ask your doctor or nurse:
  • “Has my HbA1c actually changed?”
  • “What does this mean for me right now?”
  • “Do I need to do anything differently?”
• Take your time to process any new information
• Reach out for support if you need it

If you’d like help understanding your HbA1c results or what these changes mean in your situation, talk with your healthcare team, contact Diabetes New Zealand (0800DIABETES) or explore more resources here on Diabetes Info NZ.

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Page Updated: 29 March 2026

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YOUR DIABETES HEALTHCARE
Annual Review
Medication and Supplies
Types of Insulin
Lab Tests
The HbA1c Test
Changes to HbA1c Diagnostic Criteria
Eye Examinations
Standards and Guidelines
Support and Advocacy

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