Billing code 20501: Sinus tract injectionMedicare rate & RVUs

Injection of contrast into a draining sinus tract to define its course for diagnosis, commonly as part of a fistulogram or sinogram.

CMS RVU26DEffective Oct 1, 2026109 payment localities867 Medicare services in 2024

Medicare pays $135.61 for 20501 nationally in the office and $31.06 in a hospital or facility. Local office rates run $119.17–$185.22.

Medicare rate · 20501

Sinus tract injection

Work RVUs
0.74
Total RVUs
4.06
Global days
000

National rate · 2026

$135.61

Office setting, before claim adjustments.

See every locality for 20501 →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
  1. Medicare rate
  2. What 20501 covers
  3. By payment locality
  4. Rate map
  5. How it’s calculated
  6. Payment rules
  7. Similar codes
  8. Related codes
  9. Billing questions
  10. Sources

What 20501 covers

The clinician introduces contrast into an existing sinus tract to outline its path and show where it leads. This is used in evaluating a draining tract, such as one that persists after surgery or infection. A surgeon or other clinician familiar with the tract may perform the injection in an office, procedure room, or facility; radiology staff may provide the associated imaging service. The injection helps distinguish the tract’s course and connections from what can be established by examination alone.

Report 20501 for the diagnostic injection, not for therapeutic instillation into the tract. Documentation should identify the tract, the diagnostic purpose, and the injection performed; report the radiologic examination separately when it is performed and documented. The code has a 0-day global period, so same-day preoperative and postoperative care is included. When multiple procedures are performed in the same session, the highest-valued procedure is paid in full and others are subject to the standard 50% reduction. Modifier 50 is inappropriate. Medicare does not pay an assistant at surgery; co-surgeons and team surgery 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 20501 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

$119.17 to $185.22

$119.17$152.19$185.22
One dot per payment locality, office / nonfacility. Hover a dot to see the locality; select it to open that rate.

109 of 109 payment localities

20501 office and facility rates by payment locality
Payment localityOfficeFacility
Alabama$121.02$29.55
Alaska*$153.97$42.63
Arizona$131.91$30.60
Arkansas$119.17$29.36
Atlanta$137.89$31.67
Austin$141.69$31.08
Bakersfield$145.58$31.00
Baltimore/Surr. Cntys$144.48$32.31
Beaumont$125.67$30.54
Brazoria$134.31$30.71

20501 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.

$119.17

$165.29

Color shows the midpoint of each state’s locality range.

View every state and territory as a table
20501 office rate range by state
State / territoryOffice rate rangeLocalities
AK$153.971
AL$121.021
AR$119.171
AZ$131.911
CA$145.36–$185.2229
CO$142.341
CT$144.951
DC$156.531
DE$134.191
FL$132.01–$143.633
GA$124.33–$137.892
GU$149.501
HI$149.501
IA$124.971
ID$125.691
IL$127.48–$140.524
IN$126.481
KS$124.031
KY$123.361
LA$123.03–$129.522
MA$141.28–$157.422
MD$136.97–$156.533
ME$126.04–$133.772
MI$126.47–$133.412
MN$137.111
MO$120.57–$130.403
MS$119.911
MT$135.601
NC$127.491
ND$134.221
NE$125.791
NH$139.771
NJ$146.81–$154.692
NM$127.071
NV$135.331
NY$129.49–$159.715
OH$126.181
OK$123.471
OR$134.48–$147.452
PA$126.58–$140.952
PR$136.771
RI$139.411
SC$127.011
SD$134.061
TN$124.651
TX$125.67–$141.698
UT$128.861
VA$133.07–$156.532
VI$136.771
VT$133.371
WA$141.12–$161.062
WI$129.431
WV$122.391
WY$135.001

How the 20501 rate is calculated

Each of 20501’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 · 20501

RVUs × geographic indexes × conversion factor

Work0.74

0.74 RVUs× 1.000 GPCI

Practice expense3.25

3.25 RVUs× 1.000 GPCI

Malpractice0.07

0.07 RVUs× 1.000 GPCI

Adjusted RVUs

4.0600

Conversion factor

$33.4009

Medicare rate

$135.61

Every GPCI starts at 1.000, the national rate. Enter a ZIP or drag a slider.

Payment rules and modifiers for 20501

The CMS indicators that decide how 20501 is paid alongside other services.

CMS payment indicators · 20501

Sinus tract injection

RuleCMS valueWhat it means
Global period000Same-day global: pre- and post-op care on the day of the procedure is included.
Multiple procedures2Standard reduction: highest-valued procedure at 100%, others at 50%.
Bilateral (modifier 50)0The 150% bilateral adjustment doesn’t apply.
Assistant at surgery (80/81/82/AS)1Not paid (statutory restriction).
Co-surgeons (62)0Not permitted.
Team surgery (66)0Not permitted.
Professional/technical0Physician service: no professional/technical split.

What modifiers do to the payment

Modifier 51 · payment effect

With and without the modifier

20501 without 51 · national office

$135.61

Sinus tract injection

20501-51 · Second procedure: 50%

$67.81

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%).

When to use modifier 51

20501 compared with similar codes

Compare codes · National

4 codes, side by side

  • 20501

    Sinus tract injection0.74 wRVU

    $135.61

  • 20500

    Sinus tract injection1.25 wRVU

    $128.59−$7.02

  • 76080

    Fistula imaging0.53 wRVU

    $58.79−$76.82

  • 49424

    Cavity contrast study0.74 wRVU

    $171.01+$35.40

How to choose

20500Sinus tract injection
20501 is the diagnostic injection used to outline a sinus tract. 20500 describes therapeutic injection into the tract.
76080Fistula imaging
76080 represents the radiologic examination of the sinus tract; 20501 represents the injection that helps produce the study.
49424Cavity contrast study
49424 concerns contrast evaluation through an existing percutaneous drainage catheter. Use 20501 for diagnostic injection into a sinus tract.

20501 billing questions

When should 20501 be chosen instead of 20500?

Use 20501 when contrast is injected to map a sinus tract for diagnosis. Use 20500 when material is injected therapeutically into the tract.

Can the imaging service be reported separately?

Yes. When a radiologic examination of the tract is performed and documented, the imaging service may be reported separately, such as with 76080.

Does 20501 have a global period?

It has a 0-day global period. Same-day preoperative and postoperative care is included.

Should modifier 50 be appended for two tracts?

No. CMS identifies bilateral adjustment as inappropriate for this code. Do not use modifier 50 to represent bilateral anatomy.

How are multiple procedures in the same session paid?

The highest-valued procedure is paid in full, and the other procedures are subject to the standard multiple procedure reduction, with payment at 50%.

Can an assistant surgeon or co-surgeon be reported?

Medicare does not pay an assistant at surgery for this code. Co-surgeons and team surgery are not permitted.

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
RVUs for 20501PPRRVU2026_Oct_nonQPP.csv, line 1,753 (RVU26D)

Open CMS sourceHow we calculate rates

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