Billing code 21920: Soft-tissue biopsyMedicare rate & RVUs in Washington
Reports operative sampling of a superficial soft-tissue abnormality of the back or flank when tissue is obtained for diagnostic examination.
Medicare pays $272.17–$307.48 for 21920 in the office in Washington, from Rest Of Washington to Seattle (King Cnty). 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 21920 covers
A surgeon or other qualified proceduralist obtains tissue from a superficial soft-tissue abnormality of the back or flank for diagnosis. The service is used when the procedure samples the abnormality rather than removing it as a therapeutic excision. The documented site and depth distinguish this service from biopsy of a deeper soft-tissue lesion.
Report the biopsy when the operative record supports sampling of superficial tissue and identifies the back or flank site. If the lesion is removed rather than sampled, select the applicable excision code based on the tissue depth and size criteria. This minor procedure has a 10-day global period, which includes related postoperative visits during that period. When multiple procedures are performed in the same session, the highest-valued procedure is paid in full and the others are subject to the standard 50% multiple-procedure reduction. Modifier 50 is inappropriate; assistant-at-surgery services are not paid, 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 21920 pays more and less in Washington
| Payment locality | Office | Facility |
|---|---|---|
| Rest Of Washington | $272.17 | $144.15 |
| Seattle (King Cnty) | $307.48 | $158.30 |
How the 21920 rate is calculated
Each of 21920’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 · 21920
RVUs × geographic indexes × conversion factor
Work2.06
2.06 RVUs× 1.000 GPCI
Practice expense5.54
5.54 RVUs× 1.000 GPCI
Malpractice0.30
0.30 RVUs× 1.000 GPCI
Adjusted RVUs
7.9000
Conversion factor
$33.4009
Medicare rate
$263.87
Every GPCI starts at 1.000, the national rate. Enter a ZIP or drag a slider.
Payment rules and modifiers for 21920
21920 has a 10-day global period: related visits in that window are included in the surgery payment.
CMS payment indicators · 21920
Soft-tissue biopsy
| Rule | CMS value | What it means |
|---|---|---|
| Global period | 010 | Minor procedure: the day of the procedure plus 10 days after are included. |
| Multiple procedures | 2 | Standard reduction: highest-valued procedure at 100%, others at 50%. |
| 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. |
| Split (54/55/56) | 0.10/0.80/0.10 | Share of the payment for pre-op, the procedure itself, and post-op care. |
Global surgery period · 21920
Soft-tissue biopsy
10-day global period ends
Oct 11, 2026
Covers Oct 1, 2026 through Oct 11, 2026 (11 days).
Visit on Oct 31, 2026
After the global period ends: visits and procedures are billed normally.
What modifiers do to the payment
Modifier 51 · payment effect
With and without the modifier
21920 without 51 · national office
$263.87
Soft-tissue biopsy
21920-51 · Second procedure: 50%
$131.94
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%).
21920 compared with similar codes
Compare codes · National
4 codes, side by side
How to choose
- 21925Soft-tissue biopsy
- Choose 21920 for sampling superficial back or flank soft tissue; 21925 applies when the sampled tissue is deep.
- 21930Soft-tissue excision
- 21930 describes excision of a subcutaneous back or flank lesion smaller than 3 cm. Use 21920 when the service is a biopsy rather than excision.
- 21931Back mass excision
- 21931 describes excision of a subcutaneous back or flank lesion 3 cm or larger. The distinction from 21920 is excision versus diagnostic sampling, not simply whether tissue is sent for pathology.
21920 billing questions
How does 21920 differ from 21925?
21920 is for a superficial back or flank soft-tissue biopsy. Use 21925 when the sampled soft tissue is deep.
Should 21920 be reported when the entire mass is removed?
No. When the lesion is excised rather than sampled, choose the applicable excision code based on its depth and size.
Are related postoperative visits separately reported during the global period?
Related postoperative visits for 10 days are included in the 10-day global period.
Can modifier 50 be used for biopsies on both sides of the back?
No. The bilateral adjustment does not apply to 21920, and modifier 50 is inappropriate.
How are other procedures in the same session paid?
The highest-valued procedure is paid in full, and the other procedures are subject to the standard 50% multiple-procedure reduction.
Can an assistant or co-surgeon be billed for this procedure?
Assistant-at-surgery services are not paid for 21920. Co-surgeon and team-surgery billing 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
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