TSH Blood Test
May 15, 2026
TSH Blood Test
A TSH (thyroid stimulating hormone) blood test is the primary screening test for thyroid function—when your thyroid is underactive, TSH rises as your pituitary gland tries to stimulate more thyroid hormone production; when it's overactive, TSH falls. TSH is highly sensitive to thyroid changes, often becoming abnormal before thyroid hormone levels themselves.
At Blood Test London, TSH testing costs from £245 with results in 2-3 days. A doctor always reviews every result.
Understanding TSH
What TSH Tells You
TSH Level | What It Means |
|---|---|
High TSH | Thyroid is UNDERACTIVE (hypothyroidism) |
Low TSH | Thyroid is OVERACTIVE (hyperthyroidism) |
Normal TSH | Thyroid is functioning normally |
Reference Range
TSH (mIU/L) | Interpretation |
|---|---|
0.4-4.0 | Normal range |
4.0-10 | Subclinical hypothyroidism |
Above 10 | Overt hypothyroidism |
Below 0.4 | Possible hyperthyroidism |
Below 0.1 | Likely hyperthyroidism |
TSH vs Full Thyroid Panel
Test | What It Adds |
|---|---|
TSH only | Screening—catches most problems |
+ Free T4 | Confirms and quantifies hypothyroidism |
+ Free T3 | Active hormone—conversion issues |
+ Antibodies | Autoimmune thyroid disease |
For symptoms, we recommend full panel. For screening, TSH alone may suffice.
Our Thyroid Testing Options
TSH Only - £245
TSH
Doctor interpretation
Thyroid Function Panel - £295
TSH, Free T4, Free T3
Full interpretation
Complete Thyroid Assessment - £395
Full thyroid panel
Thyroid antibodies (TPO, TgAb)
Detailed consultation
Book Your Test
Price: From £245
Results: 2-3 days
Doctor review: A doctor always reviews every result
Book via WhatsApp | Phone: 020 3951 3429
Blood Test London by The Wellness. TSH testing from £245. A doctor always reviews every result.