Free T4 test cost in Oxnard, CA
In Oxnard-Thousand Oaks-Ventura, CA, 1 hospital lists a cash price for free T4 (free thyroxine) thyroid blood test: from $18.50 to $18.50, with a median of $18.50. Across California, the median is $68.12 at 162 hospitals.
Cash prices at 1 facility for code 84439, as an outpatient — the setting a self-pay patient normally buys. Collected Sep 27, 2026; the hospital files themselves were last updated between Sep 1, 2026 and Sep 1, 2026.
Where each hospital's price falls
Each dot is one hospital's cash price on a scale from the lowest to the highest in Oxnard-Thousand Oaks-Ventura, CA.
Hospitals, cheapest first
| Hospital | Cash price | List price | Insurers pay | Off list | File date |
|---|---|---|---|---|---|
| Los Robles Hospital and Medical Center lowest Thousand Oaks, CA · (805) 497-2727 T4 FREE | $18.50 | $18.50 | $2.77–$18.50 | — | Sep 1, 2026 source file |
| Los Robles Hospital and Medical Center Thousand Oaks, CA · (805) 497-2727 THYROXINE FREE T4 DIALYS | $196.00 | $196.00 | $29.40–$196.00 | — | Sep 1, 2026 source file |
Outpatient: lowest $18.50, median $18.50, highest $18.50.
Cash or insurance?
At the one hospital here that publishes insurer rates for this code, the cash price is not below the highest rate a health plan has negotiated. If you have insurance but have not met your deductible, you usually pay your plan's negotiated rate, which falls somewhere in the "Insurers pay" column. Paying cash can cost less, but a cash payment usually does not count toward your deductible. Ask the hospital for both numbers before you book.
What it is
A free T4 test measures thyroxine that is not bound to proteins, the active form of the main thyroid hormone. It is usually ordered with or after a TSH test to check for an underactive or overactive thyroid and to adjust thyroid medicine.
What the price covers
The price usually covers the free T4 test only. The blood draw and the TSH test (84443) are billed separately.
4 rows held back from this comparison
They are priced below $1 or below a tenth of the national median for code 84439 ($67.56). Such a line is almost always a physician's fee billed separately, an assistant's share or a placeholder — a real charge, but not the price of the procedure itself.
| Dignity Health Camarillo, CARL-A-FT4 SP 70138 | $3.32 | file |
| Dignity Health Camarillo, CATHYROXINE FREE | $3.35 | file |
| Dignity Health Oxnard, CARL-A-FT4 SP 70138 | $3.51 | file |
| Dignity Health Oxnard, CATHYROXINE FREE | $3.53 | file |