Total Iron Binding Capacity (TIBC) in Serum
This test measures how much iron your blood can carry when bound to a protein called transferrin.
["TIBC helps assess iron status and identify potential iron deficiency or overload."]
Key facts at a glance
- LOINC
- 38285-3
- Short code
- RBC Duod fl Ql
- Synonyms
- RBC Duod fl Ql
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 4.2
- Ref high
- 5.9
- Critical range
- 2 N/A – 7 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 85041
- SNOMED
- 900000000000003001
- 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
What Is TIBC Used For?
TIBC is primarily used to evaluate iron metabolism. Low levels may suggest iron deficiency anemia, while high levels could indicate conditions like chronic inflammation or liver disease. It’s often ordered alongside other iron-related tests, such as serum iron and ferritin, to get a full picture of your iron status.
How Is TIBC Tested?
This test involves drawing blood from a vein in your arm. The blood sample is then analyzed in a lab to measure the amount of iron that can bind to transferrin, the protein responsible for transporting iron in your bloodstream.
What Might Affect Your Results?
Several factors can influence TIBC results, including medications (like certain antacids or blood thinners), chronic diseases (such as kidney disease or liver problems), and hormonal changes. If you’re taking medications or have health conditions, let your healthcare provider know so they can interpret your results accurately.
How Is TIBC Different from Other Iron Tests?
TIBC is distinct from tests like serum iron or ferritin, which measure actual iron levels in your blood. TIBC specifically assesses the *capacity* of transferrin to bind iron, helping doctors diagnose iron deficiency or excess more precisely.
Reference range
Adult males: 4.2-5.9; Females: 3.8-5.1 x 10^12/LN/A
No special preparation required. Stay well hydrated.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
TIBC
Frequently asked questions
TIBC helps identify whether your body isn’t absorbing enough iron (leading to anemia) or if there’s too much iron stored in your tissues (risking organ damage). It’s a key part of diagnosing and managing conditions like anemia, hemochromatosis, or other iron-related disorders.
A low TIBC may indicate iron deficiency, where your body isn’t producing enough transferrin to carry iron effectively. This can lead to fatigue, weakness, or anemia. Your doctor may recommend dietary changes, supplements, or further testing to address the underlying cause.
A high TIBC can suggest conditions like chronic inflammation (e.g., rheumatoid arthritis), liver disease, or certain infections. It may also occur in people with low iron stores but normal transferrin levels. Your doctor will work with your other test results to determine the best next steps.
Sources
- 1
- 2Lab Tests OnlineSource
- 3
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.
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 17, 2026. · Read our editorial policy