Reticulocyte Count levels: what's normal, high and low
Newly formed red blood cells. Reflects how actively your marrow is producing red cells.
Medically reviewed by Youmna DiStefano, MD · Last reviewed September 2026
The short answer
Reticulocyte Count is measured with a standard blood draw; no fasting is needed. A typical reference range is 30.0 – 100 10^9/L. At TestWell it's $19.99 all-in as Immature Red Blood Cell Test, results in 1–3 business days, drawn at Quest or Labcorp. An out-of-range result is a prompt to look closer, not a diagnosis.
- Units
- 10^9/L / K/uL
- Sample
- Blood draw
- Fasting
- Not required
- Results
- 1–3 business days
- Price
- $19.99
- Labs
- Quest or Labcorp · BioReference in NY/NJ
Reticulocyte Count Reference Range
These are the typical adult reference ranges used by major US labs. Your report will include the specific range used by the lab that processed your sample.
| Population | Range |
|---|---|
| age 18+ | 30.0 – 100 10^9/L |
Reference ranges are educational. Always interpret your result with the specific range printed on your lab report and discuss anything outside the range with a clinician.
Have a result in hand? analyze it with your AI assistant using these reviewed ranges, or run it through our explainer. Tools: look up another marker's range · convert lab units
What your Reticulocyte Count result may mean
Often reflects recovery from blood loss or anemia, or response to treatment.
What a high Reticulocyte Count means: causes, symptoms, next steps ↓Can reflect marrow suppression, iron/B12/folate deficiency, or kidney disease (low erythropoietin).
What a low Reticulocyte Count means: causes, symptoms, next steps ↓Educational only — not a diagnosis. Many factors can influence a single result. Discuss anything that concerns you with a healthcare provider.
What does a high Reticulocyte Count mean?
Reticulocytes are brand-new red cells. A high count means the bone marrow is responding — appropriately to blood loss, hemolysis or recovering iron/B12/folate deficiency, or to a low-oxygen environment such as altitude or lung disease. In someone with anemia, a high reticulocyte count is good news about the marrow and points the search toward loss or destruction of red cells rather than under-production.
Common causes of a high Reticulocyte Count
- Recovery from bleeding or after starting iron, B12 or folate treatment
- Hemolytic anemia (autoimmune, sickle cell, G6PD, spherocytosis)
- Altitude, chronic hypoxia, smoking
- Erythropoietin therapy or EPO-secreting tumors, testosterone
- Pregnancy (mild)
Ordered from most to least common.
Symptoms that can go with it
- Those of the underlying anemia: fatigue, breathlessness, pallor
- Yellow eyes and dark urine with hemolysis
What clinicians usually check next
- CBC, LDH, bilirubin, haptoglobin (hemolysis work-up)
- Stool blood test, menstrual history and iron studies for loss
- Hematology review if hemolysis is confirmed
Follow-up tests at TestWell: CBC with Differential ($21.99), LDH (Lactate Dehydrogenase) ($19.99), Haptoglobin ($101.99).
Is a high reticulocyte count bad?
It means the marrow is working hard — the question is why. After blood loss or starting iron it is the desired response; with a falling hemoglobin and high LDH it points to hemolysis.
Educational only — not a diagnosis. A single result outside the range is a prompt to look closer with a clinician.
What does a low Reticulocyte Count mean?
A low reticulocyte count in someone with anemia means the marrow is not making enough new red cells: iron, B12 or folate deficiency before treatment, chronic kidney disease (too little erythropoietin), chronic inflammation, bone-marrow suppression by medications or infection, and primary marrow disorders such as aplastic anemia or myelodysplasia. With a normal hemoglobin, a low-normal count is simply not needed.
Common causes of a low Reticulocyte Count
- Untreated iron, B12 or folate deficiency
- Chronic kidney disease (low erythropoietin)
- Anemia of chronic disease/inflammation, hypothyroidism
- Bone-marrow suppression: chemotherapy, some antibiotics and anticonvulsants, alcohol, parvovirus B19
- Aplastic anemia, myelodysplastic syndrome, marrow infiltration (less common)
Ordered from most to least common.
Symptoms that can go with it
- Fatigue, breathlessness, pallor; frequent infections or bruising if other cell lines are affected
What clinicians usually check next
- Ferritin, B12, folate, kidney function, TSH
- Peripheral smear; CBC trend
- Hematology referral (possible marrow evaluation) when the count stays low without a nutritional or renal cause
Follow-up tests at TestWell: CBC with Differential ($21.99), TSH (Thyroid Stimulating Hormone) ($26.99), TSH + Free T4 ($27.99), Ferritin ($24.99), Folate (Vitamin B9) ($32.99).
Seek care promptly if
- Low reticulocytes with a rapidly falling hemoglobin, or with low platelets and white cells — prompt evaluation
What is the reticulocyte production index?
A correction of the count for how severe the anemia is. A raw count can look 'normal' while still being inadequate for a low hemoglobin; the index below 2 means under-production.
Educational only — not a diagnosis. A single result outside the range is a prompt to look closer with a clinician.
How do you get a Reticulocyte Count test?
Order online, a licensed physician reviews the requisition, and you walk into a nearby lab for the draw. Reticulocyte Count is available on its own or inside these panels — panels cost less per marker when you want the fuller picture.
| Option | Includes | Price |
|---|---|---|
| Immature Red Blood Cell Test | This marker only | $19.99 |
| Comprehensive Anemia Workup | 8 tests | $169.99 |
Quest vs. Labcorp for Reticulocyte Count: which lab should you pick?
Both are CLIA-certified national labs and the result is clinically equivalent, so pick whichever location is closer. Your report will print that lab's own reference range, which can differ slightly from the table above.
| Lab | Available | Price |
|---|---|---|
| Quest Diagnostics | Yes | $19.99 |
| Labcorp | Yes | $19.99 |
| BioReference (NY & NJ) | Yes | $17.99 |
Need help choosing a location? Use the lab finder to see draw sites near your ZIP.
Related Blood Health biomarkers
Markers commonly tested alongside Reticulocyte Count.
Frequently asked
What does a high Reticulocyte Count mean?
Reticulocytes are brand-new red cells. A high count means the bone marrow is responding — appropriately to blood loss, hemolysis or recovering iron/B12/folate deficiency, or to a low-oxygen environment such as altitude or lung disease. In someone with anemia, a high reticulocyte count is good news about the marrow and points the search toward loss or destruction of red cells rather than under-production.
Is a high reticulocyte count bad?
It means the marrow is working hard — the question is why. After blood loss or starting iron it is the desired response; with a falling hemoglobin and high LDH it points to hemolysis.
What does a low Reticulocyte Count mean?
A low reticulocyte count in someone with anemia means the marrow is not making enough new red cells: iron, B12 or folate deficiency before treatment, chronic kidney disease (too little erythropoietin), chronic inflammation, bone-marrow suppression by medications or infection, and primary marrow disorders such as aplastic anemia or myelodysplasia. With a normal hemoglobin, a low-normal count is simply not needed.
What is the reticulocyte production index?
A correction of the count for how severe the anemia is. A raw count can look 'normal' while still being inadequate for a low hemoglobin; the index below 2 means under-production.
Do I need a doctor's order to test my reticulocyte count?
No. TestWell's licensed physician network reviews and approves your order — usually within minutes. You can place an order online without an in-person visit or a referral from your own doctor.
How long does it take to get Reticulocyte Count results?
Most Reticulocyte Count results are available in 1–3 business days after your specimen arrives at the lab. You'll get an email the moment your results are ready, with everything viewable in your TestWell portal.
How much does a Reticulocyte Count test cost?
Our Immature Red Blood Cell Test starts at $19.99. That's the all-in price — no copays, no insurance hoops, no surprise bills. HSA and FSA cards are accepted.
Do I need to fast before my Reticulocyte Count test?
Fasting is not required for the Reticulocyte Count test. You can have your blood drawn any time of day.
Which lab will process my Reticulocyte Count test?
Your test will be processed by Quest Diagnostics, Labcorp, or BioReference depending on which is closest to you and which lab carries the test. All three are CLIA-certified and trusted by hospitals nationwide. You'll choose your lab during checkout from 4,000+ locations.
What can throw off a Reticulocyte Count result?
Recent blood donation can change a Reticulocyte Count result without anything being wrong. Recent blood donation can shift reticulocytes — note recent donation if a CBC shows changes in cell size or variation. Each is explained on our physician-reviewed "Before your test" pages; when one applies, remove it and retest.
Ready to test your reticulocyte count?
Order in two minutes, get physician-approved, and visit a lab the same day. Starts at $19.99.