Magnesium test cost in Knoxville, TN — inpatient
In Knoxville, TN, 4 hospitals list a cash price for magnesium blood test as an inpatient: from $6.27 to $44.22, with a median of $30.53. The lowest listed price is at Roane County Medical Center — $24.26 less than the median here. Across Tennessee, the median is $11.85 at 44 hospitals.
Cash prices at 4 facilities across 4 cities for code 83735, as an inpatient (admitted to hospital) . Collected Sep 23, 2026; the hospital files themselves were last updated between Aug 5, 2026 and Aug 27, 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 Knoxville, TN.
Hospitals, cheapest first
| Hospital | Cash price | List price | Insurers pay | Off list | File date |
|---|---|---|---|---|---|
| Roane County Medical Center lowest Harriman, TN · (865) 316-1000 MAGNESIUM | $6.27 | $19.00 | $3.02–$17.10 | 67% | Aug 5, 2026 source file |
| Fort Sanders Regional Medical Center Knoxville, TN · (865) 541-1101 MAGNESIUM | $16.83 | $51.00 | $3.02–$45.90 | 67% | Aug 5, 2026 source file |
| Methodist Medical Center of Oak Ridge Oak Ridge, TN · (865) 835-1000 MAGNESIUM | $44.22 | $134.00 | $3.02–$120.60 | 67% | Aug 5, 2026 source file |
| Fort Loudoun Medical Center Lenoir City, TN · (865) 271-6000 MAGNESIUM | $44.22 | $134.00 | $3.02–$120.60 | 67% | Aug 27, 2026 source file |
Inpatient: lowest $6.27, median $30.53, highest $44.22 — a 7.1× difference within the same market.
As an outpatient, the same code is billed by 6 facilities here, median $21.11 — that is the price to compare if you are not being admitted.
Cash or insurance?
At 4 of 4 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 magnesium test measures the level of magnesium in the blood. Doctors order it for muscle cramps or weakness, an irregular heartbeat, low potassium or calcium that does not correct, and for people on diuretics, long-term acid-reducing drugs or with kidney disease.
What the price covers
The price usually covers running the test. The blood draw (36415) is often billed as a separate line.