Lab tests CPT 86431 Outpatient

Rheumatoid factor test cost in San Jose, CA

In San Jose-Sunnyvale-Santa Clara, CA, 4 hospitals list a cash price for rheumatoid factor (RF) test: from $45.36 to $131.00, with a median of $68.88. The lowest listed price is at Kaiser Foundation Hospital - San Jose and 1 other hospital — $23.52 less than the median here. Across California, the median is $13.20 at 93 hospitals.

Cash prices at 4 facilities across 4 cities for code 86431, as an outpatient — the setting a self-pay patient normally buys. Collected Sep 23, 2026; the hospital files themselves were last updated between Mar 31, 2026 and Apr 1, 2026.

Lowest$45.36Kaiser Foundation Hospital - San Jose + 1 more
Median$68.88half pay less
Highest$131.00in this market
Difference2.9×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 San Jose-Sunnyvale-Santa Clara, CA.

median
Lowest $45.36Highest $131.00

Hospitals, cheapest first

HospitalCash price List priceInsurers payOff listFile date
Kaiser Foundation Hospital - San Jose lowest San Jose, CA · (408) 972-7000 RHEUMATOID FACTOR QUANTITATIVE $45.36 $81.00 $5.00–$15.00 44% —
source file
Kaiser Foundation Hospital - Santa Clara lowest Santa Clara, CA · (408) 236-6400 RHEUMATOID FACTOR QUANTITATIVE $45.36 $81.00 $5.00–$15.00 44% —
source file
Stanford Health Care Stanford, CA · (650) 723-4000 HC Rheumatoid Factor Quant $92.40 $231.00 — 60% Apr 1, 2026
source file
Lucile Salter Packard Children's Hospital at Stanford Palo Alto, CA · (650) 497-8000 HC Rheumatoid Factor Quant $131.00 $262.00 $127.31 50% Mar 31, 2026
source file

Outpatient: lowest $45.36, median $68.88, highest $131.00 — a 2.9× difference within the same market.

As an inpatient, the same code is billed by 3 facilities here, median $45.36. 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 0 of 3 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.

2 rows held back from this comparison

They are priced below $1 or below a tenth of the national median for code 86431 ($38.28). 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.

El Camino Hospital Mountain View, CAHC 006502 RHEUMATOID FACTOR *3 $0.75 file
El Camino Hospital Mountain View, CAHC 056499 SYSTEMIC LUPUS PROFILE RF 7/7 *3 $1.16 file