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Hemoglobin A1c from capillary blood (24-hour average)

Published: August 9, 2026Updated: August 16, 2026

This test measures the average level of hemoglobin A1c in your blood over the past 2–3 months, reflecting your long-term blood sugar control.

Quick summary

["HbA1c helps track diabetes management and long-term glucose levels."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
80414-6
Short code
HC/AC from Campbell 1991
Synonyms
HC/AC from Campbell 1991
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
us-estimated-from-campbell
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

Why Is This Test Done?

Your healthcare provider may order this test to monitor how well your blood sugar is controlled over time, especially if you have diabetes or are at risk for it. It’s a key part of managing conditions like prediabetes, type 1 diabetes, or type 2 diabetes.

How Is the Sample Collected?

A small amount of blood is taken from your finger using a sterile needle. This is called capillary blood sampling. The test measures the percentage of hemoglobin that is bound to glucose (hemoglobin A1c) in your blood.

What Does the Test Result Mean?

Results are typically reported as a percentage (e.g., 5.7%, 6.4%, 7.5%). While specific ranges can vary by lab, higher percentages generally indicate poorer long-term blood sugar control. Your provider will interpret results in the context of your overall health and treatment plan.

What Are Common Causes of Abnormal Results?

Factors like recent blood loss, certain medications (e.g., iron supplements), or conditions affecting red blood cell lifespan can temporarily affect HbA1c levels. Chronic kidney disease, liver disease, or severe anemia may also influence results.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

HbA1c (Capillary)

Frequently asked questions

HbA1c is a critical marker for diagnosing diabetes (e.g., fasting glucose ≥126 mg/dL + HbA1c ≥6.5%) and assessing long-term glycemic control. It helps doctors adjust medications, lifestyle changes, or monitor complications like neuropathy or retinopathy.
This test is not affected by short-term blood sugar fluctuations (like meals or stress) and provides a more stable picture of your average blood sugar over months.
How often should I get this test?
Frequency depends on your diabetes management plan. Typically, people with type 1 diabetes get tested every 2–3 months, while those with type 2 diabetes may need testing every 3–6 months unless they have complications.
Can I eat or drink before this test?
No fasting is required for this test. However, if you’re also having other blood tests (e.g., fasting glucose), follow your provider’s instructions to avoid interfering results.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy