Free T4 test cost in Boston, MA — inpatient
In Boston-Cambridge-Newton, MA-NH, 7 hospitals list a cash price for Free T4 (free thyroxine) thyroid blood test as an inpatient: from $15.12 to $45.00, with a median of $22.40. The lowest listed price is at Boston Medical Center South — $7.28 less than the median here. Across Massachusetts, the median is $43.62 at 19 hospitals.
Cash prices at 7 facilities across 5 cities for code 84439, as an inpatient (admitted to hospital) . Collected Sep 23, 2026; the hospital files themselves were last updated between — and —.
Where each hospital's price falls
Each dot is one hospital's cash price on a scale from the lowest to the highest in Boston-Cambridge-Newton, MA-NH.
Hospitals, cheapest first
| Hospital | Cash price | List price | Insurers pay | Off list | File date |
|---|---|---|---|---|---|
| Boston Medical Center South lowest Brockton, MA HC Chg Assay of Free Thyroxine | $15.12 | $33.59 | $7.95–$394.86 | 55% | — source file |
| Boston Medical Center Brighton Boston, MA HC Chg Assay of Free Thyroxine | $17.20 | $38.22 | $7.95–$475.07 | 55% | — source file |
| Tufts Medical Center Boston, MA HC Assay of Free Thyroxine - T4 Free | $22.40 | $32.00 | $8.40–$39.15 | 30% | — source file |
| Lowell General Hospital Lowell, MA HC Assay of Free Thyroxine - T4 Free | $22.40 | $32.00 | $11.20–$37.02 | 30% | — source file |
| Melrosewakefield Healthcare Melrose, MA HC Assay of Free Thyroxine - T4 Free | $22.40 | $32.00 | $11.20–$530.75 | 30% | — source file |
| Boston Medical Center Boston, MA HC Chg Assay of Free Thyroxine | $42.30 | $94.00 | $7.80–$512.54 | 55% | — source file |
| Cambridge Health Alliance Cambridge, MA HC T4,Free | $45.00 | $45.00 | $7.95–$62.21 | — | — source file |
Inpatient: lowest $15.12, median $22.40, highest $45.00 — a 3.0× difference within the same market.
As an outpatient, the same code is billed by 8 facilities here, median $22.40 — that is the price to compare if you are not being admitted.
Cash or insurance?
At 7 of 7 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 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.