Rheumatoid factor test cost in Boise City, ID — inpatient
In Boise City, ID, 4 hospitals list a cash price for rheumatoid factor (RF) test as an inpatient: from $13.84 to $29.90, with a median of $21.87. The lowest listed price is at St Luke's Regional Medical Center and 1 other hospital — $8.03 less than the median here. Across Idaho, the median is $13.84 at 9 hospitals.
Cash prices at 4 facilities across 2 cities for code 86431, as an inpatient (admitted to hospital) . Collected Sep 23, 2026; the hospital files themselves were last updated between Mar 31, 2026 and Mar 31, 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 Boise City, ID.
Hospitals, cheapest first
| Hospital | Cash price | List price | Insurers pay | Off list | File date |
|---|---|---|---|---|---|
| St Luke's Regional Medical Center lowest Boise, ID · (208) 381-2222 | $13.84 | $13.84 | — | — | — source file |
| St Luke's Nampa Medical Center lowest Nampa, ID · (208) 505-2000 | $13.84 | $13.84 | — | — | — source file |
| Saint Alphonsus Medical Center - Nampa Nampa, ID · (208) 463-5000 HC Rheumatoid Factor Quantitative | $29.90 | $46.00 | $4.90–$41.40 | 35% | Mar 31, 2026 source file |
| Saint Alphonsus Regional Medical Center - Boise Boise, ID · (208) 367-2121 HC Rheumatoid Factor Quantitative | $29.90 | $46.00 | $4.90–$46.00 | 35% | Mar 31, 2026 source file |
| Saint Alphonsus Medical Center - Nampa Nampa, ID · (208) 463-5000 HC Warde Rheumatoid Factor Quantitative Body Fluid | $42.90 | $66.00 | $4.90–$59.40 | 35% | Mar 31, 2026 source file |
| Saint Alphonsus Regional Medical Center - Boise Boise, ID · (208) 367-2121 HC Warde Rheumatoid Factor Quantitative | $42.90 | $66.00 | $4.90–$66.00 | 35% | Mar 31, 2026 source file |
| Saint Alphonsus Regional Medical Center - Boise Boise, ID · (208) 367-2121 HC Warde Rheumatoid Factor Quantitative Body Fluid | $42.90 | $66.00 | $4.90–$66.00 | 35% | Mar 31, 2026 source file |
| Saint Alphonsus Medical Center - Nampa Nampa, ID · (208) 463-5000 HC Warde Rheumatoid Factor Quantitative | $42.90 | $66.00 | $4.90–$59.40 | 35% | Mar 31, 2026 source file |
| St Luke's Regional Medical Center Boise, ID · (208) 381-2222 | $44.00 | $44.00 | — | — | — source file |
| St Luke's Nampa Medical Center Nampa, ID · (208) 505-2000 | $44.00 | $44.00 | — | — | — source file |
| Saint Alphonsus Regional Medical Center - Boise Boise, ID · (208) 367-2121 HC Labcorp Rheumatoid Factor Quantitative | $53.30 | $82.00 | $4.90–$82.00 | 35% | Mar 31, 2026 source file |
| Saint Alphonsus Medical Center - Nampa Nampa, ID · (208) 463-5000 HC Labcorp Rheumatoid Factor Quantitative | $53.30 | $82.00 | $4.90–$73.80 | 35% | Mar 31, 2026 source file |
Inpatient: lowest $13.84, median $21.87, highest $29.90 — a 2.2× difference within the same market.
As an outpatient, the same code is billed by 4 facilities here, median $21.87 — that is the price to compare if you are not being admitted.
Cash or insurance?
At 2 of 2 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
Rheumatoid factor is an antibody found in many people with rheumatoid arthritis. The test is part of the workup for joint pain and swelling.
What the price covers
The price usually covers running the test. The blood draw (36415) is often billed as a separate line.