Reticulocyte % levels: what's normal, high and low
The percentage of red blood cells that are immature (newly produced).
Medically reviewed by Youmna DiStefano, MD · Last reviewed September 2026
The short answer
Reticulocyte % is measured with a standard blood draw; no fasting is needed. A typical reference range is 0.500 – 2.50 %. TestWell offers panels that include Reticulocyte %, drawn at Quest or Labcorp. An out-of-range result is a prompt to look closer, not a diagnosis.
Testing for Reticulocyte %
This marker is reported as part of a panel rather than as a standalone test. Browse the panels that include it.
Browse tests- Units
- %
- Sample
- Blood
- Fasting
- Not required
- Results
- 1–3 business days
- Labs
- Quest or Labcorp
Reticulocyte % 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+ | 0.500 – 2.50 % |
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
Related Blood Health biomarkers
Markers commonly tested alongside Reticulocyte %.
Frequently asked
Do I need a doctor's order to test my reticulocyte %?
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 % results?
Most Reticulocyte % 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.
Where can I order a Reticulocyte % test?
TestWell offers panels that include Reticulocyte % alongside related markers. Browse our test catalog to find the panel that fits your goals.
Do I need to fast before my Reticulocyte % test?
Fasting is not required for the Reticulocyte % test. You can have your blood drawn any time of day.
Which lab will process my Reticulocyte % 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.
Ready to test your reticulocyte %?
Order in two minutes, get physician-approved, and visit a lab the same day.