Total T4 test cost in Key West, FL
In Key West-Key Largo, FL, 3 hospitals list a cash price for total thyroxine (T4) blood test: from $54.15 to $142.35, with a median of $142.35. The lowest listed price is at Lower Keys Medical Center — $88.20 less than the median here. Across Florida, the median is $75.20 at 171 hospitals.
Cash prices at 3 facilities across 3 cities for code 84436, as an outpatient — the setting a self-pay patient normally buys. Collected Sep 27, 2026; the hospital files themselves were last updated between Mar 30, 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 Key West-Key Largo, FL.
Hospitals, cheapest first
| Hospital | Cash price | List price | Insurers pay | Off list |
|---|---|---|---|---|
| Lower Keys Medical Center lowest Key West, FL · (305) 294-5531 THYROXINE T4,TOTAL File of Apr 1, 2026 · source file | $54.15 | $200.55 | $5.50–$200.55 | 73% |
| Fishermens Health Marathon, FL · (305) 434-1000 T4 (thyroxine)-total File of Mar 30, 2026 · source file | $142.35 | $219.00 | $6.72–$219.00 | 35% |
| Mariners Hospital Tavernier, FL · (305) 434-3000 T4 (thyroxine)-total File of Mar 30, 2026 · source file | $142.35 | $219.00 | $6.72–$219.00 | 35% |
Outpatient: lowest $54.15, median $142.35, highest $142.35 — a 2.6× difference within the same market.
As an inpatient, the same code is billed by 3 facilities here, median $142.35. 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 3 of 3 hospitals that publish insurer rates for this code here, the cash price is below the highest rate a health plan has negotiated, and at none is it 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 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.
1 row held back from this comparison
It is priced below $1 or below a tenth of the national median for code 84436 ($51.35). 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.
| Hospital | Cash price | File |
|---|---|---|
| Lower Keys Medical Center Key West, FLL1149 T4 CEDIA | $0.74 | file |