Free T4 test cost in St. Louis, MO
In St. Louis, MO-IL, 12 hospitals list a cash price for free T4 (free thyroxine) thyroid blood test: from $39.91 to $167.04, with a median of $96.66. The lowest listed price is at Gateway Regional Medical Center — $56.75 less than the median here. Across Missouri, the median is $87.90 at 30 hospitals.
Cash prices at 12 facilities across 10 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 24, 2026 and Apr 24, 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 St. Louis, MO-IL.
Hospitals, cheapest first
| Hospital | Cash price | List price | Insurers pay | Off list | File date |
|---|---|---|---|---|---|
| Gateway Regional Medical Center lowest Granite City, IL · (618) 798-3000 THYROXINE T4, FREE | $39.91 | $66.52 | $66.52 | 40% | — source file |
| Ranken Jordan Home for Convalescent Crippled Children Hospital Maryland Heights, MO · (314) 872-6400 T4, Free, Direct Dialysis | $40.10 | $50.12 | — | 20% | Apr 24, 2026 source file |
| Ranken Jordan Home for Convalescent Crippled Children Hospital Maryland Heights, MO · (314) 872-6400 T4, Free | $40.10 | $50.12 | — | 20% | Apr 24, 2026 source file |
| Mercy Hospital St Louis Saint Louis, MO T4 Thyroxine Free | $48.10 | $74.00 | $8.12–$20.30 | 35% | — source file |
| Shriners Childrens - St Louis Saint Louis, MO · (314) 432-3600 THYROXINE (THYROID CHEMICAL); FREE | $70.80 | $70.80 | $5.08–$15.50 | — | — source file |
| Mercy Hospital South Saint Louis, MO · (314) 525-1000 T4 Thyroxine Free | $84.50 | $130.00 | $8.45–$130.00 | 35% | — source file |
| Mercy Hospital Jefferson Festus, MO T4 Thyroxine Free | $90.35 | $139.00 | $9.04–$139.00 | 35% | — source file |
| St Josephs Hospital Hospital Sisters Third Order of St Francis Breese, IL · (618) 526-4511 HC T4 FREE | $102.96 | $143.00 | $9.02–$143.00 | 28% | — source file |
| Mercy Hospital Lincoln Troy, MO · (636) 528-8551 T4 Thyroxine Free | $115.05 | $177.00 | $11.51–$177.00 | 35% | — source file |
| Mercy Hospital Washington Washington, MO T4 Thyroxine Free | $125.45 | $193.00 | $8.12–$15.25 | 35% | — source file |
| St Elizabeths Hospital of the Hospital Sisters of the Third Order of St Francis O'Fallon, IL HC T4 FREE | $127.44 | $177.00 | $9.02–$177.00 | 28% | — source file |
| St Josephs Hospital of the Hospital Sisters of the Third Order of St Francis Highland, IL · (618) 651-2600 HC T4 FREE | $136.80 | $190.00 | $18.04–$190.00 | 28% | — source file |
| Hshs Holy Family Hospital Greenville, IL · (618) 664-1230 HC T4 FREE | $167.04 | $232.00 | $9.02–$232.00 | 28% | — source file |
Outpatient: lowest $39.91, median $96.66, highest $167.04 — a 4.2× difference within the same market.
As an inpatient, the same code is billed by 8 facilities here, median $115.20. 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 8 of 11 hospitals that publish insurer rates for this code here, the cash price is below the highest rate a health plan has negotiated, and at 1 it is below every plan's rate. 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.