T3 Uptake Blood Test

Compare labs

Feature	Labcorp	Quest Diagnostics
Price	$6.49	$3.49
Results in	~2 business days	~5 business days
Sample type	Blood Serum	Blood Serum
Require fasting	No	No

About the test

T3 Uptake is a test that indirectly estimates the number of available binding sites on thyroid-binding proteins, primarily thyroid-binding globulin (TBG). It is used alongside total T4 to calculate the Free Thyroxine Index (FTI), helping to assess thyroid function and differentiate between thyroid and binding protein abnormalities.

Included biomarkers & Reference ranges

Biomarker	Reference range
T3 Uptake An older test used, together with total T4, to estimate free thyroid hormone levels by assessing binding protein capacity.	22–35 %

Reference ranges vary by lab, age, and sex (M/F). Your report shows your exact range. Click any biomarker to see its optimal range and what your results mean.

How it works

1. Order online No referral or insurance
2. Get a requisition By email in 24–72 hours
3. Visit a draw center Bring a matching photo ID
4. Get results Securely by email

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

Consultations

Not sure how to read your results? We can help.

Schedule a consultation with a Hormunity specialist. We’ll walk through every marker, interpret what it means for you, and map out the next steps for your care.

Book a specialist