Good to knowOne result rarely tells the whole story. Your provider looks at your results together with your symptoms, exam, and other tests.
What the test is
It's often done with ferritin. Iron levels change during the day and after meals, so a morning fasting sample is best.
What it measures
- Serum iron
- Total iron-binding capacity (TIBC) or transferrin
- Transferrin saturation (the percent of transferrin carrying iron)
Why it's done
- To look into anemia
- To check for hemochromatosis
- To follow iron treatment
Getting ready and what happens
- Your provider may ask you to fast for 12 hours and test in the morning.
- Don't take iron supplements for 24 hours before, unless told otherwise.
How the test is done
- A health worker cleans the skin, puts a band around your arm, and draws blood from a vein with a small needle. It takes a few minutes.
What the results mean
| Result | Typical range for adults |
|---|---|
| Serum iron | About 60 to 170 mcg/dL |
| TIBC | About 240 to 450 mcg/dL |
| Transferrin saturation | About 20% to 50% |
Normal ranges vary from lab to lab and can differ by age, sex, and pregnancy. Your report lists your lab's own range next to each result. A result a little outside the range is often not a problem.
Iron deficiency
Usually shows low iron, high TIBC, and low transferrin saturation, along with low ferritin.
Iron overload
Usually shows high iron and transferrin saturation over about 45%, with high ferritin. Genetic testing for hemochromatosis may follow.
Anemia from chronic disease
Iron and TIBC are both low, while ferritin is normal or high.
Questions to ask your provider
- What do my results mean for me?
- Do I need to repeat this test or have other tests?
- Do my results point to iron deficiency or overload?
- Do I need a ferritin test or genetic test?
Risks
A blood draw is very safe. You may have slight pain or a small bruise where the needle went in.
Related conditions
Related medicines
Related tests
Sources
Last updated 2026-11-13.