Free T4 test cost in Santa Rosa, CA
In Santa Rosa-Petaluma, CA, 4 hospitals list a cash price for free T4 (free thyroxine) thyroid blood test: from $55.85 to $102.48, with a median of $56.23. The lowest listed price is at Providence Santa Rosa Memorial Hospital and 1 other hospital — $0.38 less than the median here. Across California, the median is $68.12 at 104 hospitals.
Cash prices at 4 facilities across 3 cities for code 84439, as an outpatient — the setting a self-pay patient normally buys. Collected Sep 23, 2026; the hospital files themselves were last updated between Apr 1, 2026 and Apr 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 Santa Rosa-Petaluma, CA.
Hospitals, cheapest first
| Hospital | Cash price | List price | Insurers pay | Off list | File date |
|---|---|---|---|---|---|
| Providence Santa Rosa Memorial Hospital lowest Santa Rosa, CA · (707) 525-5300 HC ASSAY OF FREE THYROXINE CDM | $55.85 | $109.50 | — | 49% | Apr 1, 2026 source file |
| Petaluma Valley Hospital lowest Petaluma, CA · (707) 778-1111 HC ASSAY OF FREE THYROXINE CDM | $55.85 | $109.50 | — | 49% | Apr 1, 2026 source file |
| Healdsburg Hospital Healdsburg, CA · (707) 431-6500 HC ASSAY OF FREE THYROXINE CDM | $56.61 | $111.00 | — | 49% | Apr 1, 2026 source file |
| Petaluma Valley Hospital Petaluma, CA · (707) 778-1111 HC ASSAY OF FREE THYROXINE LAB | $57.12 | $112.00 | — | 49% | Apr 1, 2026 source file |
| Petaluma Valley Hospital Petaluma, CA · (707) 778-1111 HC ASSAY OF FREE THYROXINE CDM | $57.12 | $112.00 | — | 49% | Apr 1, 2026 source file |
| Healdsburg Hospital Healdsburg, CA · (707) 431-6500 HC ASSAY OF FREE THYROXINE LAB | $66.30 | $130.00 | — | 49% | Apr 1, 2026 source file |
| Providence Santa Rosa Memorial Hospital Santa Rosa, CA · (707) 525-5300 HC ASSAY OF FREE THYROXINE LAB | $74.46 | $146.00 | — | 49% | Apr 1, 2026 source file |
| Providence Santa Rosa Memorial Hospital Santa Rosa, CA · (707) 525-5300 HC ASSAY OF FREE THYROXINE CDM | $74.46 | $146.00 | — | 49% | Apr 1, 2026 source file |
| Kaiser Foundation Hospital - Santa Rosa Santa Rosa, CA · (707) 571-4000 ASSAY OF FREE THYROXINE | $102.48 | $183.00 | $8.00–$25.00 | 44% | — source file |
Outpatient: lowest $55.85, median $56.23, highest $102.48 — a 1.8× difference within the same market.
As an inpatient, the same code is billed by 4 facilities here, median $56.23. Inpatient and outpatient prices are not comparable and are kept on separate pages: the inpatient charge covers admission, not the same purchase.
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.
2 rows held back from this comparison
They are priced below $1 or below a tenth of the national median for code 84439 ($60.00). 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.
| Providence Santa Rosa Memorial Hospital Santa Rosa, CAHC ASSAY OF FREE THYROXINE LAB | $5.10 | file |
| Petaluma Valley Hospital Petaluma, CAHC ASSAY OF FREE THYROXINE LAB | $5.10 | file |