Order Serum Iron Blood Test from JustLabs for $5 ($23 all-in for a single-test order: $5 + one $18 lab & physician order fee per order). Price includes lab processing at Quest Diagnostics. No insurance required.
Serum iron measures the iron moving through your blood at the moment of the draw. It swings through the day, so on its own it says little about your iron stores; ferritin, or iron with TIBC, usually answers the real question better.
Iron is a mineral your body needs to make hemoglobin, the protein in red blood cells that carries oxygen. A serum iron test measures how much iron is circulating in your blood, most of it bound to a transport protein called transferrin.
On its own, serum iron is a limited test. It reflects iron in transit, not iron in storage, and it changes a lot from hour to hour: Quest notes that iron values fall by about 30% over the course of the day, and recent intake, birth control pills, estrogen and other medicines can shift it. A single value can therefore look normal in someone who is running low on stores, or low in someone who is not.
That is why two other tests on JustLabs are usually the better choice. Ferritin reflects your iron stores and is the standard first test for iron deficiency, although inflammation can raise it. Iron and Total Iron Binding Capacity (iron + TIBC) adds TIBC and the calculated iron saturation, which is what clinicians use to look for iron overload such as hemochromatosis. A single serum iron makes sense mainly when a clinician has asked for it, or when you are tracking this one value alongside a ferritin you already have.
For accurate results, Quest asks for a morning draw in a fasting state. Book an early appointment at a Quest Patient Service Center, and results are posted to your private JustLabs dashboard, usually within 1-3 business days.
Price
$5
All-in
$23
incl. $18 lab & physician fee
Results
1-3 business days
Fasting
12+ hrs
What's Measured
What This Test Measures
This test measures the total amount of iron in your serum, in micrograms per deciliter (mcg/dL), most of which is bound to transferrin. It does not measure stored iron (ferritin), the blood's capacity to carry iron (TIBC), or the share of transferrin carrying iron (transferrin saturation). Those come from the Ferritin and Iron and TIBC tests.
Who Should Consider This Test
People whose clinician has asked specifically for a serum iron level, and people who already have a ferritin or iron + TIBC result and want to follow serum iron alongside it. If you are trying to find out whether you are low in iron, for example because of fatigue, heavy periods, pregnancy or a diet low in iron, ferritin is usually the better first test. If you are concerned about iron overload or a family history of hemochromatosis, iron + TIBC (which gives transferrin saturation) is more useful than serum iron alone.
Health Insights
Conditions Screened
Related Symptoms
When to Get Tested
In the morning, after fasting overnight. Quest specifies morning collection from a fasting patient, because iron levels drop by about 30% during the day and fat in the blood from a recent meal can interfere with the test. For follow-up testing, use the same early time of day so results are comparable.
Fasting Required
This test requires fasting for accurate results. Please follow these instructions:
- Do not eat or drink anything except water for 12-12 hours before your blood draw.
- Water is allowed and encouraged - stay hydrated!
- Schedule your lab visit in the morning for convenience.
- Continue taking any prescribed medications unless advised otherwise by your doctor.
Understanding Your Results
Quest's adult reference ranges are 50-195 mcg/dL for men aged 20-29, 50-180 for men 30 and older, 40-190 for women aged 20-49 and 45-160 for women 50 and older (children have separate ranges). A low serum iron can point toward iron deficiency, for example from long-term digestive tract bleeding, heavy periods, poor absorption, low dietary intake or pregnancy, but it is not proof of it, because levels swing during the day. A high serum iron can be seen with hemochromatosis (iron overload), hemolytic anemia, liver disease, iron poisoning or frequent transfusions, and also after recent iron intake. Because one number says little about stores, clinicians usually confirm with ferritin and with TIBC and transferrin saturation. Review your result with a clinician before starting or stopping iron. JustLabs results are informational and do not replace medical care.
What to Expect
After placing your order, we send it straight to Quest Diagnostics — there is no consent form to sign and no partner email to wait for. Your requisition is usually ready to download from your dashboard within about an hour, and you can book your blood draw at any Quest Diagnostics location.
The blood draw typically takes just a few minutes. Results are usually available within 1-3 business days and will appear in your secure JustLabs dashboard.
Our results include reference ranges and easy-to-understand indicators showing whether your values are within normal limits.
How much does the Serum Iron test cost?
The Serum Iron test costs $5 at JustLabs — $23 all-in, since the $18 lab & physician order fee is charged once per order, however many tests you add. The price is fixed before your blood draw; no insurance or doctor visit needed.
| Option | Price | Order all-in | Notes |
|---|---|---|---|
| Serum Iron at JustLabsDrawn at Quest Diagnostics | $5 | $23 | Includes the one $18 fee, charged once per order |
Paying with an HSA or FSA? See which lab tests qualify
Frequently Asked Questions
Hospital cash price: $100–$200
$5
+ $18 order fee · $23 all-inOne $18 fee per order covers your Quest blood draw and the independent physician order, however many tests you add.
- Results in 1-3 business days
- Fasting required (12 hours)
- Physician order included
No insurance needed · HSA/FSA eligible
- Physician-ordered
- CLIA-certified Quest lab
- Drawn at Quest Diagnostics
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