TSH Blood Test
This page explains the tsh blood test, what it measures, and how to arrange it. A TSH blood test measures thyroid-stimulating hormone, a signal from your pituitary gland that tells your thyroid how much hormone to make. It is ordered to check for an underactive or overactive thyroid and to monitor thyroid treatment.
- Sample type
- blood
- Category
- Hormone
- Turnaround
- 1-3 business days
- Price
- $39
- Referral
- Not required
A TSH blood test measures thyroid-stimulating hormone, a signal from your pituitary gland that tells your thyroid how much hormone to make. It is ordered to check for an underactive or overactive thyroid and to monitor thyroid treatment.
What it measures
- TSH (thyroid-stimulating hormone) — The main marker; high or low levels can suggest thyroid problems.
- Free T4 (thyroxine) — Sometimes added to see how much active thyroid hormone is available.
- Free T3 (triiodothyronine) — Less often checked; helps assess thyroid function in some cases.
- Thyroid antibodies — May be tested if autoimmune thyroid disease is suspected.
Who it is for
A healthcare provider typically orders a TSH test if you have symptoms like fatigue, weight changes, or a fast or slow heartbeat, or to monitor thyroid medication.
Preparation
No fasting is usually required. Tell your provider about any thyroid medicines or supplements you take, as timing may matter.
Results and what they mean
Results are reported as a number with a reference range. Your clinician interprets the result along with your symptoms and history. This is general information, not medical advice; discuss your results with a qualified healthcare professional.
How to order this test
- Choose the test and place a confidential order online.
- Select a certified collection site and pick a time that suits you.
- Have your specimen collected — most draws take only a few minutes.
- Review results in a secure portal, typically within 1–3 days.
Preparation, hours, and pricing vary by site; confirm details directly with the lab before your visit.
Availability by state
Direct-access online ordering for the tsh blood test is available in most states. It is currently unavailable in 6 states:
Everywhere else you can order confidentially and collect your sample at a certified site. Browse by state →
Frequently asked questions
Do I need to fast for a TSH test?
No, fasting is not typically needed. You can eat and drink normally unless your provider gives other instructions.
What can affect my TSH level?
Thyroid medicines, biotin supplements, pregnancy, and some other medications can affect results. Share all supplements and medicines with your provider.
How soon will I get my results?
Most results are available within 1–3 business days, but this can vary by lab.
Can I take my thyroid medication before the test?
Ask your provider. Some recommend taking it after the blood draw, while others say it does not matter.