CPT code 97018: Paraffin therapy, superficial heat modality2026 Medicare rate & RVUs in California
Paraffin bath therapy applies therapeutic heat, commonly to a hand or wrist, as a physical or occupational therapy modality.
Medicare pays $6.24–$7.70 for 97018 in the office in California, from Chico, CA to San Benito County, CA. Which amount applies depends on the service address.
Medicare allowed amount for participating (non-QP) physicians, before deductible, coinsurance and claim adjustments. Not a patient’s bill or a hospital charge.
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On this page 9 sections
What 97018 covers
Paraffin bath therapy uses warmed paraffin wax to deliver superficial heat to a body area. Physical and occupational therapists commonly use it for a hand or wrist affected by stiffness or pain, often before therapeutic movement or hand-function activities. The patient immerses the area in the wax or has wax applied, and the therapist manages the treatment and monitors the area.
Report 97018 for the paraffin modality itself, not for exercise or other skilled treatment performed during the visit. Documentation should identify the treated area, the clinical reason for heat, and the treatment provided. This is a therapy service, so a professional-component modifier does not apply. When multiple therapy units are reported for the same patient on the same day, CMS reduces practice expense for the second and later units.
This summary was written with AI assistance from CMS physician fee schedule data and checked against the CMS billing rules shown here. Rates on this page come directly from CMS files.
Where 97018 pays more and less in California
The same RVUs, adjusted for each area’s costs. Open a locality for its calculation, history and nearby areas.
29 payment localities
$6.24 to $7.70
29 of 29 payment localities
| Payment locality | Office | Facility |
|---|---|---|
| Bakersfield, CA | $6.27 | Unavailable |
| Chico, CA | $6.24 | Unavailable |
| El Centro, CA | $6.25 | Unavailable |
| Fresno, CA | $6.24 | Unavailable |
| Hanford, CA | $6.24 | Unavailable |
| Los Angeles, CA | $6.65 | Unavailable |
| Madera, CA | $6.24 | Unavailable |
| Marin County, CA | $7.53 | Unavailable |
| Merced, CA | $6.24 | Unavailable |
| Modesto, CA | $6.24 | Unavailable |
| Napa, CA | $7.14 | Unavailable |
| Oxnard, CA | $6.61 | Unavailable |
| Redding, CA | $6.24 | Unavailable |
| Rest of California | $6.24 | Unavailable |
| Riverside, CA | $6.35 | Unavailable |
| Sacramento, CA | $6.53 | Unavailable |
| Salinas, CA | $6.50 | Unavailable |
| San Benito County, CA | $7.70 | Unavailable |
| San Diego, CA | $6.64 | Unavailable |
| San Francisco, CA | $7.52 | Unavailable |
| San Luis Obispo, CA | $6.40 | Unavailable |
| Santa Clara County, CA | $7.66 | Unavailable |
| Santa Cruz, CA | $6.69 | Unavailable |
| Santa Maria, CA | $6.52 | Unavailable |
| Santa Rosa, CA | $6.75 | Unavailable |
| Stockton, CA | $6.24 | Unavailable |
| Vallejo, CA | $7.13 | Unavailable |
| Visalia, CA | $6.24 | Unavailable |
| Yuba City, CA | $6.24 | Unavailable |
How the 97018 rate is calculated
Each of 97018’s three RVUs is multiplied by a geographic index (GPCI) for the payment locality, added up, and multiplied by the conversion factor. Drag the indexes or enter a ZIP to see what moves the rate.
How the rate is built · 97018
RVUs × geographic indexes × conversion factor
Work0.06
0.06 RVUs× 1.000 GPCI
Practice expense0.11
0.11 RVUs× 1.000 GPCI
Malpractice0.01
0.01 RVUs× 1.000 GPCI
Adjusted RVUs
0.1800
Conversion factor
$33.4009
Medicare rate
$6.01
Every GPCI starts at 1.000, the national rate. Enter a ZIP or drag a slider.
Payment rules and modifiers for 97018
The CMS indicators that decide how 97018 is paid alongside other services.
CMS payment indicators · 97018
Paraffin therapy, superficial heat modality
| Rule | CMS value | What it means |
|---|---|---|
| Global period | XXX | The global surgery concept doesn’t apply. |
| Multiple procedures | 5 | Therapy reduction: practice expense of the second and later units is reduced. |
| Bilateral (modifier 50) | 0 | The 150% bilateral adjustment doesn’t apply. |
| Assistant at surgery (80/81/82/AS) | 0 | Not paid without supporting documentation. |
| Co-surgeons (62) | 0 | Not permitted. |
| Team surgery (66) | 0 | Not permitted. |
| Professional/technical | 7 | Therapy service: the split doesn’t apply. |
What modifiers do to the payment
Modifier CQ · payment effect
With and without the modifier
97018 without CQ · national office
$6.01
Paraffin therapy, superficial heat modality
97018-CQ · Allowed amount unchanged
$6.01
Medicare cuts its own payment by 15% after the patient’s 20% coinsurance; the allowed amount stays the same. On $100 allowed: $20 coinsurance, then Medicare pays $68 instead of $80.
97018 compared with similar codes
Compare codes · National
4 codes, side by side
How to choose
- 97010Pack therapyHot or cold
- Choose 97018 when warmed paraffin wax is applied. Choose 97010 when the treatment uses hot or cold packs.
- 97022Whirlpool therapyAgitated water immersion
- 97018 describes paraffin wax heat; 97022 describes whirlpool treatment using water immersion.
- 97034Contrast bathsEach 15 minutes
- 97034 is for contrast bath treatment alternating warm and cold immersion. 97018 is for paraffin bath therapy.
97018 billing questions
When should 97018 be chosen over hot or cold packs?
Use 97018 when paraffin wax is the heat-delivery method. Hot or cold packs are reported with 97010 when packs, rather than a paraffin bath, provide the modality.
Is 97018 reported per 15 minutes?
The code represents paraffin bath therapy and is not a 15-minute timed modality code. Do not calculate units from the timed structure used by codes such as 97034.
Can therapeutic exercise be reported in the same visit?
Yes, when the therapist separately provides and documents skilled therapeutic exercise. The paraffin modality alone does not describe that exercise.
Should modifier 26 be appended?
No. CMS identifies 97018 as a therapy service for which the professional-component modifier does not apply.
What documentation supports reporting 97018?
Record the treated body area, the condition or functional problem prompting heat, and that paraffin therapy was administered. Document separately any distinct skilled treatment performed during the encounter.
How does the therapy multiple procedure reduction affect 97018?
When multiple therapy units are reported on the same day, CMS reduces practice expense for the second and later units. The reduction concerns practice expense, not a change in the service documented.
Where these rates come from
FeeBase calculates base physician payments from CMS work, practice-expense and malpractice RVUs, adjusted by each locality’s geographic indexes and the conversion factor. Services without a published rate are labeled, never given a made-up amount. Amounts are Medicare allowed amounts before claim adjustments: not a patient’s bill or a commercial rate.
CMS RVU26D · effective Oct 1, 2026 through the day before Jan 1, 2027
Show the CMS file lines behind this rate
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