Iron and Total Iron-binding Capacity (TIBC) CPT: 83550


Fe and TIBC

TIBC and Iron

Total Iron-binding Capacity (TIBC)

Transferrin Saturation

Unsaturated Iron-binding Capacity (UIBC)

Test Includes

Percent of saturation; serum iron; total iron binding capacity; unsaturated iron binding capacity

Expected Turnaround Time

Within 1 day

Specimen Requirements


Serum (preferred) or plasma (lithium heparin only). EDTA plasma causes decreased results.


2 mL

Minimum Volume

0.5 mL


Gel-barrier tube, transport tube, or green-top (heparin) tube; do notuse EDTA or oxalate anticoagulants.


Separate serum or plasma from cells within 45 minutes of collection.

Storage Instructions

Maintain specimen at room temperature.

Stability Requirements

Temperature Period
Room Temperature 14 days
Refrigerated 14 days
Frozen 14 days
Freeze/thaw/ cycles Stable x 3

Patient Information

Along with other iron tests, to assess your body’s ability to transport iron in the blood; to help diagnose iron-deficiency or iron overload.

When you have low hemoglobin and hematocrit on a complete blood count (CBC); when your healthcare practitioner suspects you may have too much iron (overload) or too little iron (deficiency) in the body.

A blood sample drawn from a vein in your arm.

You may be instructed to have your blood drawn in the morning and/or fast for 12 hours before the test; in this case, only water is allowed. Follow any instructions from your healthcare practitioner and/or from the laboratory performing the test.