Billing code 88365: In situ hybridizationMedicare rate & RVUs
Reports a manual in situ hybridization probe stain, including FISH testing on tissue or cytology specimens to identify targeted genetic changes.
Medicare pays $169.01 for 88365 nationally in the office. Local office rates run $148.88–$233.27.
Medicare rate · 88365
In situ hybridization
Swap in your local Medicare rate.
- Work RVUs
- 0.86
- Total RVUs
- 5.06
- Global days
- XXX
National rate · 2026
$169.01
Office setting, before claim adjustments.
See every locality for 88365 → · Billed by an NP, PA or therapist? →
Medicare allowed amount for participating (non-QP) physicians, before deductible, coinsurance and claim adjustments. Not a patient’s bill or a hospital charge.
On this page 10 sections
What 88365 covers
This service covers laboratory staining and hybridization of a tissue or cytology specimen with a targeted nucleic acid probe. Fluorescence in situ hybridization (FISH) can help evaluate findings such as gene amplification or rearrangement in a tumor specimen. Pathology laboratories perform the technical work; a pathologist or other qualified professional may interpret the findings and report them. The code concerns the probe-staining procedure, not morphometric analysis of the resulting signals.
Select the code based on the documented probe-staining service performed on the specimen. The record should identify the specimen, probe or target, method, and findings supporting the test. CMS recognizes separately priced professional and technical components: report modifier 26 for interpretation and report, modifier TC for equipment and staff, or neither modifier when billing the global service.
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 88365 pays more and less
The same RVUs, adjusted for each area’s costs. Open a locality for its calculation, history and nearby areas.
109 payment localities
$148.88 to $233.27
109 of 109 payment localities
| Payment locality | Office | Facility |
|---|---|---|
| Alabama | $151.16 | Unavailable |
| Alaska* | $191.97 | Unavailable |
| Arizona | $164.55 | Unavailable |
| Arkansas | $148.88 | Unavailable |
| Atlanta | $171.52 | Unavailable |
| Austin | $177.03 | Unavailable |
| Bakersfield | $182.53 | Unavailable |
| Baltimore/Surr. Cntys | $179.87 | Unavailable |
| Beaumont | $156.40 | Unavailable |
| Brazoria | $167.76 | Unavailable |
| Chicago | $171.20 | Unavailable |
| Chico | $182.40 | Unavailable |
| Colorado | $178.05 | Unavailable |
| Connecticut | $180.52 | Unavailable |
| Dallas | $168.57 | Unavailable |
| Dc + Md/Va Suburbs | $195.47 | Unavailable |
| Delaware | $167.38 | Unavailable |
| Detroit | $164.82 | Unavailable |
| East St. Louis | $158.88 | Unavailable |
| El Centro | $182.41 | Unavailable |
| Fort Lauderdale | $171.63 | Unavailable |
| Fort Worth | $167.19 | Unavailable |
| Fresno | $182.40 | Unavailable |
| Galveston | $168.09 | Unavailable |
| Hanford-Corcoran | $182.40 | Unavailable |
| Hawaii, Guam | $187.67 | Unavailable |
| Houston | $168.64 | Unavailable |
| Idaho | $157.34 | Unavailable |
| Indiana | $158.33 | Unavailable |
| Iowa | $156.57 | Unavailable |
| Kansas | $155.14 | Unavailable |
| Kentucky | $153.46 | Unavailable |
| Los Angeles-Long Beach-Anaheim (Los Angeles/Orange Cnty) | $195.34 | Unavailable |
| Madera | $182.40 | Unavailable |
| Manhattan | $194.00 | Unavailable |
| Merced | $182.40 | Unavailable |
| Metropolitan Boston | $197.10 | Unavailable |
| Metropolitan Kansas City | $160.49 | Unavailable |
| Metropolitan Philadelphia | $175.43 | Unavailable |
| Metropolitan St. Louis | $162.33 | Unavailable |
| Miami | $176.25 | Unavailable |
| Minnesota | $172.34 | Unavailable |
| Mississippi | $149.39 | Unavailable |
| Modesto | $182.40 | Unavailable |
| Montana** | $169.01 | Unavailable |
| Napa | $214.62 | Unavailable |
| Nebraska | $157.66 | Unavailable |
| Nevada** | $168.98 | Unavailable |
| New Hampshire | $174.59 | Unavailable |
| New Mexico | $157.65 | Unavailable |
| New Orleans | $160.93 | Unavailable |
| North Carolina | $159.31 | Unavailable |
| North Dakota** | $168.41 | Unavailable |
| Northern Nj | $193.17 | Unavailable |
| Nyc Suburbs/Long Island | $198.03 | Unavailable |
| Ohio | $156.90 | Unavailable |
| Oklahoma | $153.88 | Unavailable |
| Oxnard-Thousand Oaks-Ventura | $194.78 | Unavailable |
| Portland | $184.67 | Unavailable |
| Poughkpsie/N Nyc Suburbs | $183.74 | Unavailable |
| Puerto Rico | $170.53 | Unavailable |
| Queens | $196.64 | Unavailable |
| Redding | $182.40 | Unavailable |
| Rest Of California | $182.40 | Unavailable |
| Rest Of Florida | $163.38 | Unavailable |
| Rest Of Georgia | $154.16 | Unavailable |
| Rest Of Illinois | $157.46 | Unavailable |
| Rest Of Louisiana | $152.95 | Unavailable |
| Rest Of Maine | $157.49 | Unavailable |
| Rest Of Maryland | $170.89 | Unavailable |
| Rest Of Massachusetts | $176.65 | Unavailable |
| Rest Of Michigan | $157.02 | Unavailable |
| Rest Of Missouri | $149.76 | Unavailable |
| Rest Of New Jersey | $183.07 | Unavailable |
| Rest Of New York | $161.75 | Unavailable |
| Rest Of Oregon | $168.15 | Unavailable |
| Rest Of Pennsylvania | $157.53 | Unavailable |
| Rest Of Texas | $161.81 | Unavailable |
| Rest Of Washington | $176.52 | Unavailable |
| Rhode Island | $174.04 | Unavailable |
| Riverside-San Bernardino-Ontario | $182.75 | Unavailable |
| Sacramento-Roseville-Folsom | $192.28 | Unavailable |
| Salinas | $191.58 | Unavailable |
| San Diego-Chula Vista-Carlsbad | $196.71 | Unavailable |
| San Francisco-Oakland-Berkeley (Marin Cnty) | $228.30 | Unavailable |
| San Francisco-Oakland-Berkeley (San Francisco/San Mateo/Alameda/Contra Costa Cnty) | $228.27 | Unavailable |
| San Jose-Sunnyvale-Santa Clara (San Benito Cnty) | $233.27 | Unavailable |
| San Jose-Sunnyvale-Santa Clara (Santa Clara Cnty) | $233.13 | Unavailable |
| San Luis Obispo-Paso Robles | $188.39 | Unavailable |
| Santa Cruz-Watsonville | $199.09 | Unavailable |
| Santa Maria-Santa Barbara | $192.47 | Unavailable |
| Santa Rosa-Petaluma | $201.16 | Unavailable |
| Seattle (King Cnty) | $201.88 | Unavailable |
| South Carolina | $158.27 | Unavailable |
| South Dakota** | $168.34 | Unavailable |
| Southern Maine | $167.39 | Unavailable |
| Stockton | $182.40 | Unavailable |
| Suburban Chicago | $173.74 | Unavailable |
| Tennessee | $155.87 | Unavailable |
| Utah | $160.55 | Unavailable |
| Vallejo | $214.57 | Unavailable |
| Vermont | $167.12 | Unavailable |
| Virgin Islands | $170.53 | Unavailable |
| Virginia | $166.35 | Unavailable |
| Visalia | $182.40 | Unavailable |
| West Virginia | $151.19 | Unavailable |
| Wisconsin | $162.47 | Unavailable |
| Wyoming** | $168.75 | Unavailable |
| Yuba City | $182.40 | Unavailable |
88365 rates by state
Office rate range in each state. Select a state to see its payment localities.
Explore a state
Local rates. Clear comparisons.
Hover or focus a tile to see its rate range. Select it to open the state’s fee schedule.
$148.88
$207.84
Color shows the midpoint of each state’s locality range.
View every state and territory as a table
| State / territory | Office rate range | Localities |
|---|---|---|
| AK | $191.97 | 1 |
| AL | $151.16 | 1 |
| AR | $148.88 | 1 |
| AZ | $164.55 | 1 |
| CA | $182.40–$233.27 | 29 |
| CO | $178.05 | 1 |
| CT | $180.52 | 1 |
| DC | $195.47 | 1 |
| DE | $167.38 | 1 |
| FL | $163.38–$176.25 | 3 |
| GA | $154.16–$171.52 | 2 |
| GU | $187.67 | 1 |
| HI | $187.67 | 1 |
| IA | $156.57 | 1 |
| ID | $157.34 | 1 |
| IL | $157.46–$173.74 | 4 |
| IN | $158.33 | 1 |
| KS | $155.14 | 1 |
| KY | $153.46 | 1 |
| LA | $152.95–$160.93 | 2 |
| MA | $176.65–$197.10 | 2 |
| MD | $170.89–$195.47 | 3 |
| ME | $157.49–$167.39 | 2 |
| MI | $157.02–$164.82 | 2 |
| MN | $172.34 | 1 |
| MO | $149.76–$162.33 | 3 |
| MS | $149.39 | 1 |
| MT | $169.01 | 1 |
| NC | $159.31 | 1 |
| ND | $168.41 | 1 |
| NE | $157.66 | 1 |
| NH | $174.59 | 1 |
| NJ | $183.07–$193.17 | 2 |
| NM | $157.65 | 1 |
| NV | $168.98 | 1 |
| NY | $161.75–$198.03 | 5 |
| OH | $156.90 | 1 |
| OK | $153.88 | 1 |
| OR | $168.15–$184.67 | 2 |
| PA | $157.53–$175.43 | 2 |
| PR | $170.53 | 1 |
| RI | $174.04 | 1 |
| SC | $158.27 | 1 |
| SD | $168.34 | 1 |
| TN | $155.87 | 1 |
| TX | $156.40–$177.03 | 8 |
| UT | $160.55 | 1 |
| VA | $166.35–$195.47 | 2 |
| VI | $170.53 | 1 |
| VT | $167.12 | 1 |
| WA | $176.52–$201.88 | 2 |
| WI | $162.47 | 1 |
| WV | $151.19 | 1 |
| WY | $168.75 | 1 |
How the 88365 rate is calculated
Each of 88365’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 · 88365
RVUs × geographic indexes × conversion factor
Swap in your local Medicare rate.
Work 0.86Practice expense 4.17Malpractice 0.03
All indexes start at 1.000 (the national rate). Enter a ZIP or drag a slider.
Payment rules and modifiers for 88365
The CMS indicators that decide how 88365 is paid alongside other services.
CMS payment indicators · 88365
In situ hybridization
| Rule | CMS value | What it means |
|---|---|---|
| Global period | XXX | The global surgery concept doesn’t apply. |
| Multiple procedures | 0 | No multiple-procedure reduction. |
| 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 | 1 | Diagnostic test with separate professional (26) and technical (TC) components. |
What modifiers do to the payment
Modifier 26 · payment effect
With and without the modifier
88365 without 26 · national office
$169.01
In situ hybridization
88365-26 · Professional component
$40.42
Pays only the interpretation and report.
88365 compared with similar codes
Compare codes
88365 vs 88364 vs 88366 vs 88367 vs 88368: national Medicare rates
Swap in your local Medicare rate.
How to choose
- 88364ISH probe stain
- 88364 is for the initial single-probe stain procedure on a specimen. Use 88365 for an additional single-probe stain procedure.
- 88366FISH interpretation
- 88366 reports the interpretation and report for in situ hybridization; 88365 represents probe-staining work.
- 88367ISH analysis
- 88367 describes manual morphometric analysis of in situ hybridization results, not the probe-staining procedure.
- 88368ISH analysis
- 88368 describes computer-assisted morphometric analysis of in situ hybridization results, rather than the stain procedure.
88365 billing questions
How does this differ from 88364?
Both codes are in the in situ hybridization family. 88364 represents the initial single-probe stain procedure; 88365 is used for an additional single-probe stain procedure on the specimen.
Can the professional and technical work be billed separately?
Yes. Modifier 26 identifies the professional interpretation and report, while modifier TC identifies the technical work, equipment, and staff. Without either modifier, the claim represents the global service.
Does this code include interpretation and reporting?
The professional component represents interpretation and reporting. Code 88366 is the separate in situ hybridization interpretation-and-report service when that code applies.
What should the laboratory document?
Document the specimen, probe or target, staining method, and the work performed. The pathology report should support the interpretation when the professional component is billed.
When would 88367 or 88368 be more appropriate?
Those codes describe morphometric analysis of in situ hybridization results, rather than the probe-staining procedure reported with 88365.
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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