Iron, TIBC and Ferritin Panel
The Iron, TIBC and Ferritin Panel measures serum iron, total iron-binding capacity, and ferritin, and reports the derived transferrin saturation, providing a complete assessment of iron status. Its pattern distinguishes iron deficiency (low iron, high TIBC, low saturation, low ferritin), iron overload (high saturation and ferritin), and the anaemia of chronic disease.
4
Biomarkers
Blood (serum)
Sample
1–3 business days
Turnaround
Yes — morning fasting collection is preferred for reliability of serum iron and transferrin saturation, with iron supplements withheld beforehand # REVIEWER FLAG: Confirm Quest fasting and supplement-withholding guidance.
Fasting
What is the Iron Studies Panel test?
The Iron, TIBC and Ferritin Panel measures serum iron, total iron-binding capacity, and ferritin, and reports the derived transferrin saturation, providing a complete assessment of iron status. Together these values characterise iron stores, transport capacity, and availability, and their pattern distinguishes the main disorders of iron metabolism more reliably than any single marker. In the diagnostic landscape, the panel is the standard comprehensive iron assessment, used to diagnose and characterise iron deficiency, iron overload, and the anaemia of chronic disease. Its strength is in the pattern: iron deficiency shows low iron, high TIBC, low transferrin saturation, and low ferritin; iron overload shows high iron, high transferrin saturation, and high ferritin; and the anaemia of chronic disease shows low iron with normal or low TIBC and normal or raised ferritin. Ferritin is the most specific single marker of stores, but because it rises with inflammation, the full panel and the derived saturation add the context needed to interpret it. Practitioners order the panel to work up anaemia, investigate suspected overload, and clarify iron status in chronic disease.
What does the Iron Studies Panel test measure?
Serum iron measures transferrin-bound iron in transit between absorption, storage, and utilisation. It shows marked diurnal variation, is highest in the morning, and rises after recent iron intake, so it is interpreted within the panel rather than alone.
Serum iron contributes to the panel chiefly by combining with TIBC to derive transferrin saturation. On its own it is too variable to characterise iron status reliably.
Total iron-binding capacity reflects the blood's capacity to bind iron, largely determined by transferrin, the main iron-transport protein. TIBC rises when iron stores are low (the body upregulates transferrin) and falls in iron overload and chronic disease.
TIBC helps distinguish causes of abnormal iron status: a high TIBC supports iron deficiency, while a low or normal TIBC accompanies iron overload and the anaemia of chronic disease. With serum iron it yields transferrin saturation.
Transferrin saturation is calculated as serum iron divided by TIBC, expressing the proportion of iron-binding capacity occupied by iron. It integrates the two measured values into a single index of iron availability.
Transferrin saturation is a key discriminating value: a low saturation supports iron deficiency, while a high saturation (commonly >45%) is an important trigger to investigate iron overload such as hereditary haemochromatosis.
Ferritin is the principal iron-storage protein, and serum ferritin reflects total body iron stores. It is also an acute-phase reactant, rising with inflammation independent of iron status, which is the central interpretive caveat of the panel.
Ferritin is the most specific single marker of iron stores: a low value is highly specific for iron deficiency. Because inflammation raises it, a normal or high ferritin can mask deficiency, so it is interpreted alongside the rest of the panel and, where needed, CRP.
Why is the Iron Studies Panel test ordered?
- Comprehensive assessment of suspected iron deficiency or iron-deficiency anaemia, beyond ferritin alone
- Investigation of microcytic anaemia to characterise the underlying iron pattern
- Evaluation of suspected iron overload, such as hereditary haemochromatosis, where transferrin saturation and ferritin are key
- Differentiation of iron deficiency from the anaemia of chronic disease, where the pattern across markers is decisive
- Assessment of iron status in chronic kidney disease, heart failure, and other chronic conditions
- Monitoring of iron repletion or iron-overload management over time
- Evaluation of iron status in menstruating women, pregnancy, and patients with chronic blood loss
- Investigation of unexplained fatigue where a full iron assessment is warranted
Sample collection and turnaround
Sample type
Blood (serum)
Fasting required
Yes — morning fasting collection is preferred for reliability of serum iron and transferrin saturation, with iron supplements withheld beforehand # REVIEWER FLAG: Confirm Quest fasting and supplement-withholding guidance.
Collection method
Venipuncture at patient service centre
Turnaround
1–3 business days
Collection notes
Collect in the morning after an overnight fast where possible, as serum iron is highest in the morning and rises after iron intake. Withhold iron supplements for an appropriate interval beforehand. Avoid haemolysis, which falsely raises iron and saturation. Consider concurrent CRP where inflammation may affect ferritin.
Specimen requirements
Minimum 1.0 mL serum. Separate serum from cells within 2 hours of collection; avoid haemolysed specimens.
What can affect Iron Studies Panel results?
Inflammation raises ferritin and lowers serum iron, producing the pattern of the anaemia of chronic disease and potentially masking iron deficiency. Concurrent CRP helps flag this effect.
Serum iron is highest in the morning and rises after iron intake, so morning fasting collection improves reliability, particularly for transferrin saturation.
Iron therapy and transfusion raise serum iron and ferritin, so timing relative to treatment must be considered when assessing baseline status.
Hormonal factors and pregnancy alter transferrin and iron measures, affecting TIBC and transferrin saturation independent of true iron status.
Hepatocellular injury and some malignancies raise ferritin disproportionately to stores, complicating interpretation.
Haemolysis releases iron from red cells, falsely raising serum iron and the derived transferrin saturation, so haemolysed samples should be avoided.
What do Iron Studies Panel results mean?
Elevated
A high serum iron with a high transferrin saturation (commonly >45%) and a high ferritin suggests iron overload, such as hereditary haemochromatosis, warranting further evaluation. An isolated high ferritin with normal saturation more often reflects inflammation, liver disease, or malignancy than true overload.
Normal
A normal panel across all components suggests adequate iron status, though in inflammation a normal ferritin can still mask deficiency, and the saturation and TIBC should be reviewed. Results are interpreted as a pattern rather than by single values.
Reduced
Low ferritin with low serum iron, high TIBC, and low transferrin saturation is the classic pattern of iron deficiency. Low serum iron with normal or low TIBC and normal or raised ferritin suggests the anaemia of chronic disease rather than true deficiency.
Note: The panel is interpreted as a pattern: ferritin is the most specific stores marker but is an acute-phase reactant, so inflammation can mask deficiency, and the saturation and TIBC provide essential context. Serum iron is variable and reliable only within the panel and with morning fasting collection. Haemolysis falsely raises iron and saturation. Where inflammation complicates interpretation, CRP and clinical context are needed.
Frequently asked questions
It measures serum iron, total iron-binding capacity, and ferritin, and reports the derived transferrin saturation. Together these characterise iron stores, transport capacity, and availability for a complete assessment of iron status.
How to access the Iron Studies Panel test
The Iron Studies Panel reference page is free and open to all practitioners. Create a free practitioner account to see pricing, save tests to your list, and generate requisition forms. Verification takes 1–2 business days.
Create Free AccountAbout this page
Published: June 3, 2026
Last reviewed: June 3, 2026
- Camaschella C. Iron-deficiency anemia. N Engl J Med. (2015)
- Pasricha SR, et al. Iron deficiency. Lancet. (2021)
- Cullis JO, et al. Investigation and management of a raised serum ferritin. Br J Haematol. (2018)
- Kowdley KV, et al. ACG Clinical Guideline: Hereditary Hemochromatosis. Am J Gastroenterol. (2019)
This content is for licensed healthcare practitioners only and does not constitute medical advice. Clinical decisions should be based on the full clinical picture and not on any single test result.
Related tests
vitamins minerals
Ferritin
The Ferritin test measures serum ferritin, the circulating form of the body's principal iron-storage protein, as the standard indirect measure of total body iron stores. A low ferritin is the most specific routine marker of iron deficiency, while a high ferritin indicates iron overload or, commonly, an acute-phase inflammatory response.
vitamins minerals
Serum Iron
The Iron, Total (serum iron) test measures the iron bound to transferrin in the circulation, reflecting iron in transit rather than total body stores. It has limited value in isolation owing to diurnal and day-to-day variability and sensitivity to recent intake, and is most informative within iron studies, where it combines with total iron-binding capacity to derive transferrin saturation.
cardiovascular
hs-CRP
The high-sensitivity C-reactive protein (hs-CRP) test measures low concentrations of C-reactive protein in serum to assess chronic, low-grade systemic inflammation. It is used to refine cardiovascular risk stratification alongside lipid measures, with values below 1.0 mg/L indicating low risk and above 3.0 mg/L indicating high risk. Testing must be performed away from acute infection or injury.