Transferrin Test
A transferrin test measures transferrin, the protein that carries iron through the bloodstream. Clinicians often look at transferrin to help evaluate how iron is being transported around the body, as one piece of a broader iron picture.
About this test
Transferrin is a protein made mainly by the liver, and its job is to bind iron and ferry it through the blood to the tissues that need it. Where ferritin reflects stored iron, transferrin describes the transport system that moves iron from place to place.
The test is done with a routine blood draw at a patient service center. A phlebotomist collects a small sample from a vein, usually in the arm, and sends it to the laboratory.
Who might consider this test?
- Often exploring iron balance more broadly
- Sometimes because of symptoms that can be linked to iron
- Such as fatigue or low energy
Test details
| Quest code | 891 |
|---|---|
| Methodology | Immunoturbidimetric |
| Sample type | 1 mL serum |
| Collection | Quest patient service center |
Reference range
188-341 mg/dL
Reference ranges are general guidance. The range printed on your own laboratory report is the one that applies to your result.
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Additional details
What this test looks at
Transferrin describes the vehicle that moves iron through the blood. The liver adjusts how much transferrin it makes in response to the body's iron needs, so the marker reflects the transport side of iron balance. Reading it helps a clinician think about how readily iron can be carried to the places that use it.
It also helps to remember what transferrin is not. It does not describe stored iron, which is a separate question that a ferritin test addresses. That distinction is part of why transferrin and ferritin are often considered together rather than in place of one another.
How it's often used alongside other iron markers
Transferrin is frequently read as part of a wider iron evaluation. Depending on what a clinician is exploring, it may be paired with serum iron, ferritin, or total iron-binding capacity, a closely related measure of how much iron the blood can carry. Each of these describes a different part of the same system, from stored iron to circulating iron to transport capacity.
Read together, these markers offer a more complete sense of iron balance than any single one can provide. A clinician weighs the pattern across them, along with a person's history and symptoms, before drawing any conclusions.
Order online and a physician order is included — no doctor's visit and no insurance needed. Your sample is collected at a Quest Diagnostics patient service center.
Laboratory results should always be interpreted by a licensed clinician who knows your health history. This page is information about a test, not medical advice.
Frequently asked questions
What does a transferrin test measure?
It measures transferrin, the protein that carries iron through the bloodstream. Transferrin reflects the body's capacity to transport iron rather than how much iron is stored in reserve.
How is transferrin different from ferritin?
Transferrin describes the transport of iron through the blood, while ferritin reflects stored iron. Clinicians often look at both, along with other markers, to understand iron balance more completely.
How is the sample collected?
Through a routine blood draw at a patient service center. A phlebotomist takes a small sample from a vein in the arm and sends it to the laboratory for analysis.
Do I need to fast before a transferrin test?
No preparation instructions are listed for this test, though people follow any instructions their ordering clinician provides.
Is transferrin measured together with other iron tests?
Often, yes. Clinicians commonly read transferrin alongside serum iron, ferritin, and total iron-binding capacity to see the storage, circulation, and transport of iron as one connected picture.
How much is a Transferrin test?
$79, paid once at checkout. The price includes the physician's order this test requires and sample collection at a Quest patient service center.