Magnesium test cost in St. Louis, MO
In St. Louis, MO-IL, 17 hospitals list a cash price for magnesium blood test: from $7.92 to $114.48, with a median of $60.45. The lowest listed price is at Ranken Jordan Pediatric Bridge Hospital — $52.53 less than the median here. Across Missouri, the median is $47.57 at 64 hospitals.
- The median here, $60.45, is 45% above the US median of $41.60.
- That is 9.0× Medicare's 2026 national rate for the same service ($6.70).
- St. Louis, MO has the lowest median of 2 metro areas in Missouri with at least 10 hospitals pricing this code.
- 2 of 17 hospitals list a cash price equal to their full list price, with no self-pay discount.
Cash prices at 17 facilities across 15 cities for code 83735, as an outpatient — the setting a self-pay patient normally buys. Collected Sep 27, 2026; the hospital files themselves were last updated between Feb 6, 2026 and Jun 10, 2026.
Lowest$7.92Ranken Jordan Pediatric Bridge Hospital
Median$60.45half of hospitals charge less
Highest$114.48in this market
Difference14.5×highest vs lowest
Where each hospital's price falls
Each dot is one hospital's cash price on a scale from the lowest to the highest in St. Louis, MO-IL.
median
Lowest $7.92Highest $239.40
Hospitals, cheapest first
| Hospital | Cash price | List price | Insurers pay | Off list |
|---|---|---|---|---|
| Ranken Jordan Pediatric Bridge Hospital lowest Maryland Heights, MO · (314) 872-6400 Magnesium Level File of Apr 24, 2026 · source file | $7.92 | $9.90 | — | 20% |
| Carlinville Area Hospital Carlinville, IL · (217) 854-3141 URINE MAGNESIUM RANDOM File of Mar 21, 2026 · source file | $16.10 | $23.00 | $8.28–$32.86 | 30% |
| Ranken Jordan Pediatric Bridge Hospital Maryland Heights, MO · (314) 872-6400 Magnesium, 24 Hour Urine File of Apr 24, 2026 · source file | $20.15 | $25.18 | — | 20% |
| Mercy Hospital Jefferson Festus, MO · (636) 933-1000 Magnesium File of Jun 10, 2026 · source file | $24.05 | $37.00 | $2.41–$37.00 | 35% |
| Mercy Hospital St Louis Saint Louis, MO · (314) 251-6000 Magnesium File of Jun 4, 2026 · source file | $24.05 | $37.00 | $2.41–$37.00 | 35% |
| Mercy Hospital South Saint Louis, MO · (314) 525-1000 Magnesium RBC File of Jun 10, 2026 · source file | $29.25 | $45.00 | $6.03–$15.08 | 35% |
| Gateway Regional Medical Center Granite City, IL · (618) 798-3000 L910235 MAGNESIUM, URINE File of Mar 30, 2026 · source file | $40.20 | $67.00 | $67.00 | 40% |
| Touchette Regional Hospital Cahokia Heights, IL · (618) 332-3060 Magnesium File of Apr 13, 2026 · source file | $48.98 | $79.00 | $3.00–$75.00 | 38% |
| Mercy Hospital South Saint Louis, MO · (314) 525-1000 Magnesium Urine File of Jun 10, 2026 · source file | $52.00 | $80.00 | $6.03–$15.08 | 35% |
| Shriners Childrens - St Louis Saint Louis, MO · (314) 432-3600 ASSAY OF MAGNESIUM File of Mar 18, 2026 · source file | $52.70 | $52.70 | $2.81–$11.51 | — |
| Mercy Hospital Washington Washington, MO · (636) 239-8000 Magnesium Urine File of Jun 10, 2026 · source file | $60.45 | $93.00 | $6.05–$83.70 | 35% |
| Mercy Hospital Jefferson Festus, MO · (636) 933-1000 Magnesium Urine File of Jun 10, 2026 · source file | $60.45 | $93.00 | $6.05–$93.00 | 35% |
| Mercy Hospital St Louis Saint Louis, MO · (314) 251-6000 Magnesium Urine File of Jun 4, 2026 · source file | $60.45 | $93.00 | $6.05–$93.00 | 35% |
| Mercy Hospital Washington Washington, MO · (636) 239-8000 Magnesium File of Jun 10, 2026 · source file | $62.40 | $96.00 | $6.03–$11.33 | 35% |
| Community Hospital of Staunton Staunton, IL · (618) 635-2200 MAGNESIUM LEVEL File of Feb 9, 2026 · source file | $63.30 | $126.60 | $36.60–$115.21 | 50% |
| Mercy Hospital Jefferson Festus, MO · (636) 933-1000 Magnesium Stool+3 more lines at this price File of Jun 10, 2026 · source file | $70.20 | $108.00 | $6.03–$108.00 | 35% |
| Carlinville Area Hospital Carlinville, IL · (217) 854-3141 24HR URINE MAGNESIUM File of Mar 21, 2026 · source file | $73.50 | $105.00 | $37.80–$150.00 | 30% |
| Mercy Hospital South Saint Louis, MO · (314) 525-1000 Magnesium Stool File of Jun 10, 2026 · source file | $74.75 | $115.00 | $6.03–$15.08 | 35% |
| Mercy Hospital St Louis Saint Louis, MO · (314) 251-6000 Magnesium 24 Hr Urine+3 more lines at this price File of Jun 4, 2026 · source file | $76.05 | $117.00 | $6.03–$117.00 | 35% |
| Mercy Hospital Lincoln Troy, MO · (636) 528-8551 Magnesium 24 Hr Urine File of Jun 10, 2026 · source file | $76.70 | $118.00 | $5.93–$15.08 | 35% |
| Anderson Hospital Maryville, IL · (618) 288-5711 MAGNESIUM LEVEL File of Feb 6, 2026 · source file | $77.85 | $155.70 | $6.27–$140.13 | 50% |
| Jersey Community Hospital Jerseyville, IL · (618) 498-6402 Magnesium Level File of Mar 10, 2026 · source file | $78.00 | $78.00 | $40.79–$66.30 | — |
| Mercy Hospital South Saint Louis, MO · (314) 525-1000 Magnesium 24 Hr Urine File of Jun 10, 2026 · source file | $78.00 | $120.00 | $6.03–$15.08 | 35% |
| Mercy Hospital Lincoln Troy, MO · (636) 528-8551 Stone Risk Ua Magnesium File of Jun 10, 2026 · source file | $78.65 | $121.00 | $7.87–$121.00 | 35% |
| Mercy Hospital South Saint Louis, MO · (314) 525-1000 Magnesium File of Jun 10, 2026 · source file | $78.65 | $121.00 | $7.87–$121.00 | 35% |
| Mercy Hospital Lincoln Troy, MO · (636) 528-8551 Magnesium+1 more line at this price File of Jun 10, 2026 · source file | $79.30 | $122.00 | $5.93–$15.08 | 35% |
| St Josephs Hospital Hospital Sisters Third Order of St Francis Breese, IL · (618) 526-4511 ASSAY OF MAGNESIUM File of Mar 24, 2026 · source file | $79.92 | $111.00 | $3.80–$111.00 | 28% |
| Mercy Hospital Lincoln Troy, MO · (636) 528-8551 Magnesium RBC File of Jun 10, 2026 · source file | $79.95 | $123.00 | $5.93–$15.08 | 35% |
| Mercy Hospital South Saint Louis, MO · (314) 525-1000 Stone Risk Ua Magnesium File of Jun 10, 2026 · source file | $83.20 | $128.00 | $8.32–$128.00 | 35% |
| Mercy Hospital Washington Washington, MO · (636) 239-8000 Magnesium 24 Hr Urine+3 more lines at this price File of Jun 10, 2026 · source file | $83.85 | $129.00 | $6.03–$116.10 | 35% |
| Mercy Hospital Lincoln Troy, MO · (636) 528-8551 Magnesium Stool File of Jun 10, 2026 · source file | $84.50 | $130.00 | $8.45–$130.00 | 35% |
| St Josephs Hospital of the Hospital Sisters of the Third Order of St Francis Highland, IL · (618) 651-2600 ASSAY OF MAGNESIUM File of Mar 24, 2026 · source file | $102.24 | $142.00 | $8.84–$142.00 | 28% |
| Carlinville Area Hospital Carlinville, IL · (217) 854-3141 MAGNESIUM RBC (REF) File of Mar 21, 2026 · source file | $105.00 | $150.00 | $54.00–$214.29 | 30% |
| St Elizabeths Hospital of the Hospital Sisters of the Third Order of St Francis O'Fallon, IL · (618) 234-2120 HC MAGNESIUM File of Mar 24, 2026 · source file | $105.12 | $146.00 | $3.80–$146.00 | 28% |
| Hshs Holy Family Hospital Greenville, IL · (618) 664-1230 ASSAY OF MAGNESIUM File of Mar 24, 2026 · source file | $114.48 | $159.00 | $3.99–$159.00 | 28% |
| Carlinville Area Hospital Carlinville, IL · (217) 854-3141 IONIZED MAGNESIUM NOVA WHOLE BLOOD+2 more lines at this price File of Mar 21, 2026 · source file | $123.20 | $176.00 | $63.36–$251.43 | 30% |
| Gateway Regional Medical Center Granite City, IL · (618) 798-3000 Q442 MAGNESIUM File of Mar 30, 2026 · source file | $206.46 | $344.10 | $344.10 | 40% |
| Carlinville Area Hospital Carlinville, IL · (217) 854-3141 ASSOC CHG MG FECAL CATHARTIC LAX PANEL File of Mar 21, 2026 · source file | $239.40 | $342.00 | $123.12–$488.57 | 30% |
Hospital The hospital that published the price, its city and the line exactly as written in its price file.
Cash price The hospital's own price for a patient paying without insurance (“discounted cash” in its price file). Hospitals must publish it under federal law, 45 CFR 180.50. Call to confirm it before booking. More
List price The hospital's full chargemaster price (“gross charge”) before any discount. Almost nobody pays it; the gap to the cash price shows what the self-pay discount is worth. More
Insurers pay The lowest and highest rates this hospital has agreed with insurance plans for the same item, from its price file. If the cash price is below what your plan pays and you have not met your deductible, paying cash can cost you less. More
Off list How much lower the cash price is than the list price.
No cash discount This line's cash price equals the hospital's full list price. Many hospitals still reduce bills for uninsured patients: ask the billing office for its self-pay discount in writing. More
Outpatient: lowest $7.92, median $60.45, highest $114.48 — a 14.5× difference within the same market.
As an inpatient, the same code is billed by 10 facilities here, median $77.93. 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 12 of 16 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 magnesium test is, what the price covers and why prices differ: Magnesium test explained.