Billing code 46604: AnoscopyMedicare rate & RVUs in Illinois
Report this service when the clinician examines the anal canal with an anoscope and dilates a narrowed area during the procedure.
Medicare pays $637.76–$713.53 for 46604 in the office in Illinois, from Rest Of Illinois to Suburban Chicago. 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.
On this page 9 sections
What 46604 covers
A clinician advances an anoscope to inspect the anal canal and dilates a narrowed segment under direct visualization. Dilation may use a balloon, guidewire, or bougie. A typical indication is anal canal narrowing that makes passage difficult or limits examination. Colorectal surgeons and other clinicians who perform anorectal procedures may provide the service in an office or outpatient facility.
Report this code when the documented service includes both anoscopic examination and dilation; a diagnostic examination without dilation is a different service. The note should identify the narrowing and document the dilation performed and its method. Medicare assigns a 0-day global period, so same-day preoperative and postoperative care is included. When related endoscopies are performed together, endoscopy family pricing applies. Do not use modifier 50. Medicare does not pay an assistant-at-surgery claim for this service, and co-surgeon and team-surgery billing are not permitted.
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 46604 pays more and less in Illinois
The same RVUs, adjusted for each area’s costs. Open a locality for its calculation, history and nearby areas.
4 payment localities
$637.76 to $713.53
| Payment locality | Office | Facility |
|---|---|---|
| Chicago | $702.34 | $70.59 |
| East St. Louis | $645.03 | $66.71 |
| Rest Of Illinois | $637.76 | $63.84 |
| Suburban Chicago | $713.53 | $67.96 |
How the 46604 rate is calculated
Each of 46604’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 · 46604
RVUs × geographic indexes × conversion factor
Swap in your local Medicare rate.
Work 1.00Practice expense 19.51Malpractice 0.18
All indexes start at 1.000 (the national rate). Enter a ZIP or drag a slider.
Payment rules and modifiers for 46604
The CMS indicators that decide how 46604 is paid alongside other services.
CMS payment indicators · 46604
Anoscopy
| Rule | CMS value | What it means |
|---|---|---|
| Global period | 000 | Same-day global: pre- and post-op care on the day of the procedure is included. |
| Multiple procedures | 3 | Endoscopy family rules apply. |
| Bilateral (modifier 50) | 0 | The 150% bilateral adjustment doesn’t apply. |
| Assistant at surgery (80/81/82/AS) | 1 | Not paid (statutory restriction). |
| Co-surgeons (62) | 0 | Not permitted. |
| Team surgery (66) | 0 | Not permitted. |
| Professional/technical | 0 | Physician service: no professional/technical split. |
What modifiers do to the payment
Modifier 51 · payment effect
With and without the modifier
46604 without 51 · national office
$691.06
Anoscopy
46604-51 · Second procedure: 50%
$345.53
When this isn’t the highest-valued procedure in the session, Medicare pays 50% of its fee schedule amount (the highest is paid at 100%).
46604 compared with similar codes
Compare codes
46604 vs 46600 vs 46606 vs 45910: national Medicare rates
Swap in your local Medicare rate.
How to choose
- 46600Diagnostic anoscopy
- Use 46600 for diagnostic anoscopy without dilation. Report 46604 when the clinician dilates a narrowed anal canal during the examination.
- 46606Anoscopy biopsy
- 46606 describes anoscopy with biopsy. Choose it when tissue sampling is performed rather than dilation; document the actual intervention.
- 45910Rectal dilation
- 45910 describes anal sphincter dilation under anesthesia other than local. It is distinct from dilation performed with anoscopy under 46604.
46604 billing questions
When should I report this instead of diagnostic anoscopy?
Report this code when the clinician performs dilation of a narrowed anal canal during anoscopy. A diagnostic examination without dilation points to 46600.
Can I report a biopsy separately when dilation is performed?
This code represents anoscopy with dilation, not biopsy. If the clinician also takes a biopsy, document the additional work and apply the applicable coding and endoscopy family pricing rules.
Should I append modifier 50?
No. Medicare's bilateral adjustment does not apply, and modifier 50 is inappropriate for this code.
Is same-day evaluation and management work included?
The code has a 0-day global period, which includes same-day preoperative and postoperative care.
Can an assistant or co-surgeon be billed?
Medicare does not pay an assistant-at-surgery claim for this service. Co-surgeon and team-surgery billing are not permitted.
What documentation supports reporting dilation?
Document the anal canal narrowing and the dilation actually performed, including the method used. An anoscopic examination alone does not support this code.
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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