Total T4 test cost in Santa Rosa, CA
In Santa Rosa-Petaluma, CA, 5 hospitals list a cash price for total thyroxine (T4) blood test: from $15.40 to $118.00, with a median of $39.20. The lowest listed price is at Petaluma Valley Hospital and 1 other hospital — $23.80 less than the median here. Across California, the median is $39.20 at 183 hospitals.
Cash prices at 5 facilities across 3 cities for code 84436, as an outpatient — the setting a self-pay patient normally buys. Collected Sep 29, 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 |
|---|---|---|---|---|---|
| Petaluma Valley Hospital lowest Petaluma, CA · (707) 778-1111 HC THYROXINE T4 | $15.40 | $30.20 | — | 49% | Apr 1, 2026 source file |
| Providence Santa Rosa Memorial Hospital lowest Santa Rosa, CA · (707) 525-5300 HC THYROXINE T4 | $15.40 | $30.20 | — | 49% | Apr 1, 2026 source file |
| Kaiser Foundation Hospital - Santa Rosa Santa Rosa, CA · (707) 571-4000 ASSAY OF THYROXINE TOTAL | $39.20 | $70.00 | $6.00–$20.00 | 44% | — source file |
| Petaluma Valley Hospital Petaluma, CA · (707) 778-1111 HC THYROXINE T4 | $42.84 | $84.00 | — | 49% | Apr 1, 2026 source file |
| Petaluma Valley Hospital Petaluma, CA · (707) 778-1111 HC ASSAY OF THYROXINE TOTAL LAB | $42.84 | $84.00 | — | 49% | Apr 1, 2026 source file |
| Healdsburg Hospital Healdsburg, CA · (707) 431-6500 HC THYROXINE T4 | $56.61 | $111.00 | — | 49% | Apr 1, 2026 source file |
| Providence Santa Rosa Memorial Hospital Santa Rosa, CA · (707) 525-5300 HC THYROXINE T4 | $56.61 | $111.00 | — | 49% | Apr 1, 2026 source file |
| Providence Santa Rosa Memorial Hospital Santa Rosa, CA · (707) 525-5300 HC ASSAY OF THYROXINE TOTAL LAB | $56.61 | $111.00 | — | 49% | Apr 1, 2026 source file |
| Sutter Santa Rosa Regional Hospital Santa Rosa, CA · (707) 576-4000 HCHG THYROXINE (T4) | $118.00 | $118.00 | — | — | Apr 1, 2026 source file |
| Sutter Santa Rosa Regional Hospital Santa Rosa, CA · (707) 576-4000 HCHG CORE THYROXINE (T4) | $123.00 | $123.00 | — | — | Apr 1, 2026 source file |
Outpatient: lowest $15.40, median $39.20, highest $118.00 — a 7.7× difference within the same market.
As an inpatient, the same code is billed by 5 facilities here, median $39.20. 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 total T4 test measures all the thyroxine hormone in the blood, both bound and free. Most doctors now order free T4 (84439) instead, which is less affected by pregnancy and medicines.
What the price covers
The price usually covers running the test. The blood draw (36415) is often billed as a separate line.
2 rows held back from this comparison
They are priced below $1 or below a tenth of the national median for code 84436 ($52.65). 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.
| Petaluma Valley Hospital Petaluma, CAHC ASSAY OF THYROXINE TOTAL LAB | $2.23 | file |
| Providence Santa Rosa Memorial Hospital Santa Rosa, CAHC ASSAY OF THYROXINE TOTAL LAB | $2.23 | file |