Rheumatoid factor test cost in St. Louis, MO
In St. Louis, MO-IL, 15 hospitals list a cash price for rheumatoid factor (RF) test: from $20.15 to $181.44, with a median of $53.40. The lowest listed price is at Mercy Hospital St Louis and 2 other hospitals — $33.25 less than the median here. Across Missouri, the median is $49.00 at 60 hospitals.
- The median here, $53.40, is 32% above the US median of $40.48.
- That is 9.4× Medicare's 2026 national rate for the same service ($5.67).
- St. Louis, MO ranks 2nd of 2 metro areas in Missouri by median, cheapest first.
- 1 of 15 hospitals list a cash price equal to their full list price, with no self-pay discount.
Cash prices at 15 facilities across 13 cities for code 86431, 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.
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.
Hospitals, cheapest first
| Hospital | Cash price | List price | Insurers pay | Off list |
|---|---|---|---|---|
| Mercy Hospital St Louis lowest Saint Louis, MO · (314) 251-6000 Rheumatoid Factor Quantitative File of Jun 4, 2026 · source file | $20.15 | $31.00 | $5.10–$12.76 | 35% |
| Mercy Hospital Jefferson lowest Festus, MO · (636) 933-1000 Rheumatoid Factor Quantitative File of Jun 10, 2026 · source file | $20.15 | $31.00 | $2.02–$31.00 | 35% |
| Mercy Hospital South lowest Saint Louis, MO · (314) 525-1000 Rheumatoid Factor Quantitative File of Jun 10, 2026 · source file | $20.15 | $31.00 | $2.02–$31.00 | 35% |
| Gateway Regional Medical Center Granite City, IL · (618) 798-3000 RHEUMATOID FACT QUAN File of Mar 30, 2026 · source file | $33.51 | $55.85 | $55.85 | 40% |
| Touchette Regional Hospital Cahokia Heights, IL · (618) 332-3060 Rheumatoid factor; quantitative File of Apr 13, 2026 · source file | $47.74 | $77.00 | $2.92–$73.00 | 38% |
| Shriners Childrens - St Louis Saint Louis, MO · (314) 432-3600 RHEUMATOID FACTOR QUANT File of Mar 18, 2026 · source file | $49.00 | $49.00 | $3.02–$9.75 | — |
| Mercy Hospital Washington Washington, MO · (636) 239-8000 Rheumatoid Factor Quantitative File of Jun 10, 2026 · source file | $50.05 | $77.00 | $5.10–$9.60 | 35% |
| Anderson Hospital Maryville, IL · (618) 288-5711 RHEUMATOID FACTOR TITRE File of Feb 6, 2026 · source file | $53.40 | $106.80 | $5.30–$96.12 | 50% |
| Community Hospital of Staunton Staunton, IL · (618) 635-2200 RHEUMATOID FACTOR TITRE File of Feb 9, 2026 · source file | $63.30 | $126.60 | $36.60–$115.21 | 50% |
| Carlinville Area Hospital Carlinville, IL · (217) 854-3141 RHEUMATOID ARTHRITIS (RA) FACTOR REF+1 more line at this price File of Mar 21, 2026 · source file | $64.40 | $92.00 | $33.12–$131.43 | 30% |
| Carlinville Area Hospital Carlinville, IL · (217) 854-3141 ASSOC CHG RF FACTOR ISOTOPES IgM+2 more lines at this price File of Mar 21, 2026 · source file | $74.20 | $106.00 | $38.16–$151.43 | 30% |
| Mercy Hospital Lincoln Troy, MO · (636) 528-8551 Rheumatoid Factor Quantitative File of Jun 10, 2026 · source file | $74.75 | $115.00 | $5.67–$8.04 | 35% |
| St Josephs Hospital Hospital Sisters Third Order of St Francis Breese, IL · (618) 526-4511 HC RHEUMATOID FACTOR QN File of Mar 24, 2026 · source file | $85.68 | $119.00 | $5.67–$119.00 | 28% |
| Hshs Holy Family Hospital Greenville, IL · (618) 664-1230 RHEUMATOID FACTOR QUANT File of Mar 24, 2026 · source file | $100.08 | $139.00 | $5.67–$139.00 | 28% |
| St Josephs Hospital of the Hospital Sisters of the Third Order of St Francis Highland, IL · (618) 651-2600 HC RHEUMATOID FACTOR QN File of Mar 24, 2026 · source file | $112.32 | $156.00 | $11.34–$156.00 | 28% |
| Carlinville Area Hospital Carlinville, IL · (217) 854-3141 RA TEST QUANT File of Mar 21, 2026 · source file | $128.10 | $183.00 | $65.88–$261.43 | 30% |
| St Elizabeths Hospital of the Hospital Sisters of the Third Order of St Francis O'Fallon, IL · (618) 234-2120 HC RHEUMATOID FACTOR QN File of Mar 24, 2026 · source file | $181.44 | $252.00 | $5.67–$252.00 | 28% |
Outpatient: lowest $20.15, median $53.40, highest $181.44 — a 9.0× difference within the same market.
As an inpatient, the same code is billed by 8 facilities here, median $75.04. 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 11 of 15 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 rheumatoid factor test is, what the price covers and why prices differ: Rheumatoid factor test explained.