Days Set Up
Daily, 24 hours
Analytic Time

4 hours

MiChart Code
T3, Free
Soft Order Code
FT3

Test Updated:

Synonyms

Free T3
Free T3 (Triiodothyronine)
FT3
T3 Triiodothyronine Free Serum
Triiodothyronine
Triiodothyronine, Free

+ See More

Looking to order a test?

We’ve provided helpful links to make ordering easy.

Find a Requisition

All specimens should be accompanied by a requisition.

Submitting Specimens

Learn about how to properly label and where to ship specimens.

Order Kits and Supplies

MLabs provides all the supplies necessary for the collection of specimens.

Test FAQ

Visit our provider FAQ and learn about common questions to ordering tests.

Test Overview

Test Methodology

Chemiluminescent Immunoassay

Test Usage

Evaluating biochemical status of clinically euthyroid patients; further confirmatory test for hyperthyroidism monitoring thyroid replacement therapy.

Reference Range

1.9 - 3.9 pg/mL

* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Specimen Requirements

Collection Onsite

Collect specimen in SST tube.

Collection Offsite

Collect specimen in a red top or SST tube. Centrifuge, aliquot serum into a plastic vial and refrigerate up to 48 hours or freeze for longer storage.

Yellow Top Tube
Normal Volume
0.5 mL serum
Minimum Volume
0.25 mL serum

Billing Information

CPT Code
84481
Pro Fee Code
 
LOINC
3051-0

Have More Questions?

Explore our helpful billing resources:

Our High Standard

Quality that sets us apart

As the reference laboratory division of Michigan Medicine's Department of Pathology, MLabs shares the institution's commitment to applying established quality principles to clinical laboratory testing. Like other large organizations in complex, consequential fields, we rely on an established approach to monitor quality throughout the testing process.

LEARN MORE