Ammonia test cost in Baltimore, MD
In Baltimore-Columbia-Towson, MD, 7 hospitals list a cash price for ammonia blood test: from $35.26 to $73.89, with a median of $58.73. The lowest listed price is at Greater Baltimore Medical Center — $23.47 less than the median here. Across Maryland, the median is $57.90 at 14 hospitals.
Cash prices at 7 facilities across 2 cities for code 82140, as an outpatient — the setting a self-pay patient normally buys. Collected Sep 29, 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 Baltimore-Columbia-Towson, MD.
Hospitals, cheapest first
| Hospital | Cash price | List price | Insurers pay | Off list | File date |
|---|---|---|---|---|---|
| Greater Baltimore Medical Center lowest Towson, MD · (443) 849-2000 HC Ammonia | $35.26 | $35.98 | $35.26–$35.98 | 2% | — source file |
| MedStar Franklin Square Medical Center Baltimore, MD · (443) 777-7850 AMMONIA | $42.84 | $43.71 | $42.84–$43.71 | 2% | Apr 1, 2026 source file |
| MedStar Harbor Hospital Baltimore, MD · (410) 350-3201 AMMONIA | $58.30 | $59.49 | $58.30–$59.49 | 2% | Apr 1, 2026 source file |
| MedStar Good Samaritan Hospital Baltimore, MD · (443) 444-3902 AMMONIA | $58.73 | $59.93 | $58.73–$59.93 | 2% | Apr 1, 2026 source file |
| Mercy Medical Center Baltimore, MD · (410) 332-9237 HC ASSAY OF AMMONIA | $64.06 | $65.37 | $65.37–$64.06 | 2% | — source file |
| MedStar Union Memorial Hospital Baltimore, MD · (410) 554-2227 AMMONIA | $65.03 | $66.36 | $65.03–$66.36 | 2% | Apr 1, 2026 source file |
| Mt. Washington Pediatric Hospital Baltimore, MD · (410) 578-5050 AMMONIA BLOOD | $73.89 | $75.40 | $73.89–$75.40 | 2% | — source file |
Outpatient: lowest $35.26, median $58.73, highest $73.89 — a 2.1× difference within the same market.
As an inpatient, the same code is billed by 3 facilities here, median $64.06. 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 6 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 1 it is 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
An ammonia test measures ammonia in the blood. It is used for confusion or drowsiness in people with liver disease and for some rare inherited disorders in newborns.
What the price covers
The price usually covers running the test. The blood draw (36415) is often billed as a separate line.