Free T4 test cost in Madison, WI — inpatient
In Madison, WI, 2 hospitals list a cash price for Free T4 (free thyroxine) thyroid blood test as an inpatient: from $70.85 to $112.80, with a median of $91.83. The lowest listed price is at Aspirus Divine Savior Hospital — $20.98 less than the median here. Across Wisconsin, the median is $70.85 at 81 hospitals.
Cash prices at 2 facilities across 2 cities for code 84439, as an inpatient (admitted to hospital) . Collected Sep 23, 2026; the hospital files themselves were last updated between Jan 28, 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 Madison, WI.
Hospitals, cheapest first
| Hospital | Cash price | List price | Insurers pay | Off list | File date |
|---|---|---|---|---|---|
| Aspirus Divine Savior Hospital lowest Portage, WI Fac Assay of Free Thyroxine | $70.85 | $109.00 | — | 35% | Apr 1, 2026 source file |
| Aspirus Divine Savior Hospital lowest Portage, WI ASSAY OF FREE THYROXINE | $70.85 | $109.00 | — | 35% | Apr 1, 2026 source file |
| Meriter Hospital, Inc Madison, WI ASSAY OF FREE THYROXINE | $112.80 | $141.00 | $5.41–$133.95 | 20% | Jan 28, 2026 source file |
| Meriter Hospital, Inc Madison, WI HC FREE THYROXINE | $121.18 | $151.47 | $34.84–$143.90 | 20% | Jan 28, 2026 source file |
Inpatient: lowest $70.85, median $91.83, highest $112.80 — a 1.6× difference within the same market.
As an outpatient, the same code is billed by 2 facilities here, median $91.83 — that is the price to compare if you are not being admitted.
Cash or insurance?
At the one hospital here that publishes insurer rates for this code, the cash price is 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.