Magnesium test cost in Santa Rosa, CA — inpatient
In Santa Rosa-Petaluma, CA, 4 hospitals list a cash price for magnesium blood test as an inpatient: from $17.85 to $120.40, with a median of $36.72. The lowest listed price is at Providence Santa Rosa Memorial Hospital and 1 other hospital — $18.87 less than the median here. Across California, the median is $106.08 at 103 hospitals.
Cash prices at 4 facilities across 3 cities for code 83735, as an inpatient (admitted to hospital) . Collected Sep 23, 2026; the hospital files themselves were last updated between Apr 1, 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 Santa Rosa-Petaluma, CA.
Hospitals, cheapest first
| Hospital | Cash price | List price | Insurers pay | Off list | File date |
|---|---|---|---|---|---|
| Providence Santa Rosa Memorial Hospital lowest Santa Rosa, CA · (707) 525-5300 HC MAGNESIUM QUANT URINE | $17.85 | $35.00 | — | 49% | Apr 1, 2026 source file |
| Petaluma Valley Hospital lowest Petaluma, CA · (707) 778-1111 HC MAGNESIUM QUANT URINE | $17.85 | $35.00 | — | 49% | Apr 1, 2026 source file |
| Providence Santa Rosa Memorial Hospital Santa Rosa, CA · (707) 525-5300 HC ASSAY OF MAGNESIUM LAB | $34.55 | $67.75 | — | 49% | Apr 1, 2026 source file |
| Petaluma Valley Hospital Petaluma, CA · (707) 778-1111 HC ASSAY OF MAGNESIUM LAB | $34.55 | $67.75 | — | 49% | Apr 1, 2026 source file |
| Healdsburg Hospital Healdsburg, CA · (707) 431-6500 HC ASSAY OF MAGNESIUM CDM | $55.59 | $109.00 | — | 49% | Apr 1, 2026 source file |
| Kaiser Foundation Hospital - Santa Rosa Santa Rosa, CA · (707) 571-4000 ASSAY OF MAGNESIUM | $120.40 | $215.00 | $6.00–$20.00 | 44% | — source file |
Inpatient: lowest $17.85, median $36.72, highest $120.40 — a 6.7× difference within the same market.
As an outpatient, the same code is billed by 4 facilities here, median $36.72 — 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 not 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 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.
2 rows held back from this comparison
They are priced below $1 or below a tenth of the national median for code 83735 ($43.50). 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.
| Providence Santa Rosa Memorial Hospital Santa Rosa, CAHC ASSAY OF MAGNESIUM CDM | $4.30 | file |
| Petaluma Valley Hospital Petaluma, CAHC ASSAY OF MAGNESIUM CDM | $4.30 | file |