Medicare Reimbursement for CPT 21423

This page covers CPT code 21423, a physician procedure code billed to Medicare under the Physician Fee Schedule (PFS). It shows the estimated Medicare-allowed amount nationally and provides the inputs used to calculate it, with non-facility and facility settings shown separately when they differ.

Medicare allowed amount (2026)

Locality	Non-facility	Facility
National (unadjusted)	$721.79	$721.79
ALASKA* (AK)	$888.78	$888.78
ALABAMA (AL)	$655.51	$655.51
ARKANSAS (AR)	$647.33	$647.33
ARIZONA (AZ)	$702.98	$702.98
SAN FRANCISCO-OAKLAND-BERKELEY (SAN FRANCISCO/SAN MATEO/ALAMEDA/CONTRA COSTA CNTY) (CA)	$841.93	$841.93
SAN JOSE-SUNNYVALE-SANTA CLARA (SANTA CLARA CNTY) (CA)	$855.09	$855.09
OXNARD-THOUSAND OAKS-VENTURA (CA)	$762.14	$762.14
LOS ANGELES-LONG BEACH-ANAHEIM (LOS ANGELES/ORANGE CNTY) (CA)	$769.72	$769.72
NAPA (CA)	$808.18	$808.18
SAN FRANCISCO-OAKLAND-BERKELEY (MARIN CNTY) (CA)	$844.16	$844.16
VALLEJO (CA)	$804.98	$804.98
BAKERSFIELD (CA)	$731.99	$731.99
CHICO (CA)	$726.51	$726.51
FRESNO (CA)	$726.51	$726.51
HANFORD-CORCORAN (CA)	$726.51	$726.51
MADERA (CA)	$726.51	$726.51
MERCED (CA)	$726.51	$726.51
MODESTO (CA)	$726.51	$726.51
REDDING (CA)	$726.51	$726.51
RIVERSIDE-SAN BERNARDINO-ONTARIO (CA)	$747.61	$747.61
SACRAMENTO-ROSEVILLE-FOLSOM (CA)	$753.52	$753.52
SALINAS (CA)	$750.54	$750.54
SAN JOSE-SUNNYVALE-SANTA CLARA (SAN BENITO CNTY) (CA)	$864.19	$864.19
SANTA CRUZ-WATSONVILLE (CA)	$763.97	$763.97
SANTA ROSA-PETALUMA (CA)	$771.09	$771.09
STOCKTON (CA)	$726.51	$726.51
VISALIA (CA)	$726.51	$726.51
YUBA CITY (CA)	$726.51	$726.51
EL CENTRO (CA)	$726.83	$726.83
SAN DIEGO-CHULA VISTA-CARLSBAD (CA)	$761.79	$761.79
SAN LUIS OBISPO-PASO ROBLES (CA)	$739.53	$739.53
SANTA MARIA-SANTA BARBARA (CA)	$751.60	$751.60
REST OF CALIFORNIA (CA)	$726.51	$726.51
COLORADO (CO)	$731.09	$731.09
CONNECTICUT (CT)	$765.94	$765.94
DC + MD/VA SUBURBS (DC)	$802.20	$802.20
DELAWARE (DE)	$713.31	$713.31
FORT LAUDERDALE (FL)	$778.63	$778.63
MIAMI (FL)	$834.31	$834.31
REST OF FLORIDA (FL)	$741.39	$741.39
ATLANTA (GA)	$740.86	$740.86
REST OF GEORGIA (GA)	$701.64	$701.64
HAWAII, GUAM (HI)	$735.74	$735.74
IOWA (IA)	$656.57	$656.57
IDAHO (ID)	$663.06	$663.06
EAST ST. LOUIS (IL)	$763.94	$763.94
SUBURBAN CHICAGO (IL)	$782.99	$782.99
CHICAGO (IL)	$810.56	$810.56
REST OF ILLINOIS (IL)	$732.29	$732.29
INDIANA (IN)	$666.03	$666.03
KANSAS (KS)	$660.24	$660.24
KENTUCKY (KY)	$682.60	$682.60
NEW ORLEANS (LA)	$712.82	$712.82
REST OF LOUISIANA (LA)	$684.21	$684.21
METROPOLITAN BOSTON (MA)	$787.85	$787.85
REST OF MASSACHUSETTS (MA)	$730.21	$730.21
BALTIMORE/SURR. CNTYS (MD)	$765.08	$765.08
REST OF MARYLAND (MD)	$723.59	$723.59
SOUTHERN MAINE (ME)	$694.91	$694.91
REST OF MAINE (ME)	$672.81	$672.81
DETROIT (MI)	$756.10	$756.10
REST OF MICHIGAN (MI)	$703.88	$703.88
MINNESOTA (MN)	$684.49	$684.49
METROPOLITAN ST. LOUIS (MO)	$707.38	$707.38
METROPOLITAN KANSAS CITY (MO)	$701.81	$701.81
REST OF MISSOURI (MO)	$678.28	$678.28
MISSISSIPPI (MS)	$662.60	$662.60
MONTANA** (MT)	$721.66	$721.66
NORTH CAROLINA (NC)	$677.86	$677.86
NORTH DAKOTA** (ND)	$682.91	$682.91
NEBRASKA (NE)	$657.75	$657.75
NEW HAMPSHIRE (NH)	$726.03	$726.03
NORTHERN NJ (NJ)	$796.98	$796.98
REST OF NEW JERSEY (NJ)	$770.15	$770.15
NEW MEXICO (NM)	$709.81	$709.81
NEVADA** (NV)	$711.16	$711.16
MANHATTAN (NY)	$831.85	$831.85
NYC SUBURBS/LONG ISLAND (NY)	$857.77	$857.77
POUGHKPSIE/N NYC SUBURBS (NY)	$780.22	$780.22
QUEENS (NY)	$828.48	$828.48
REST OF NEW YORK (NY)	$687.20	$687.20
OHIO (OH)	$695.96	$695.96
OKLAHOMA (OK)	$674.78	$674.78
PORTLAND (OR)	$744.32	$744.32
REST OF OREGON (OR)	$701.14	$701.14
METROPOLITAN PHILADELPHIA (PA)	$753.21	$753.21
REST OF PENNSYLVANIA (PA)	$693.35	$693.35
PUERTO RICO (PR)	$724.14	$724.14
RHODE ISLAND (RI)	$731.43	$731.43
SOUTH CAROLINA (SC)	$688.95	$688.95
SOUTH DAKOTA** (SD)	$678.32	$678.32
TENNESSEE (TN)	$663.91	$663.91
BRAZORIA (TX)	$707.49	$707.49
DALLAS (TX)	$714.47	$714.47
GALVESTON (TX)	$711.24	$711.24
HOUSTON (TX)	$747.12	$747.12
BEAUMONT (TX)	$689.88	$689.88
FORT WORTH (TX)	$712.29	$712.29
AUSTIN (TX)	$732.61	$732.61
REST OF TEXAS (TX)	$699.99	$699.99
UTAH (UT)	$696.94	$696.94
VIRGINIA (VA)	$697.40	$697.40
VIRGIN ISLANDS (VI)	$724.14	$724.14
VERMONT (VT)	$686.42	$686.42
SEATTLE (KING CNTY) (WA)	$796.25	$796.25
REST OF WASHINGTON (WA)	$726.80	$726.80
WISCONSIN (WI)	$663.77	$663.77
WEST VIRGINIA (WV)	$710.32	$710.32
WYOMING** (WY)	$704.77	$704.77

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Maximum units per day (MUE)

Medicare’s Medically Unlikely Edit caps this code at 1 unit per patient per day — Date of Service Edit: Policy. Units above the MUE are denied; some MUEs can be exceeded only with appropriate documentation and modifiers where policy allows.

How the amount is calculated

Medicare's Physician Fee Schedule amount is built from three Relative Value Units (RVUs) assigned to a code: work, practice expense (PE), and malpractice (MP). Each RVU component is adjusted by Geographic Practice Cost Indices (GPCIs) specific to the provider's locality, reflecting local cost differences. The adjusted RVUs are summed and multiplied by the annual conversion factor (a dollar figure set by CMS) to produce the allowed amount. Practice-expense RVUs — and therefore the total — can differ between non-facility (e.g., office) and facility (e.g., hospital) settings because overhead costs differ by site of service.

RVUs — work 10.58, practice expense 9.07 (non-facility) / 9.07 (facility), malpractice 1.96 — × the locality GPCIs × the 2026 conversion factor of $33.40.

Good to know

This is an estimate only, not a guarantee of payment.
Medicare typically pays 80% of the allowed amount after the annual Part B deductible is met; the patient or secondary insurer is responsible for the remainder.
Actual payment varies by locality GPCIs, applicable modifiers, claims-processing adjustments, sequestration, and annual budget-neutrality changes to RVUs or the conversion factor.
This figure does not reflect bundled or multiple-procedure payment reductions, assistant-at-surgery rules, or MAC-specific policies.
Verify current rates and site-of-service rules with your Medicare Administrative Contractor (MAC) before billing or appealing a denial.

Frequently asked

Why does the Medicare amount differ by locality?

The RVUs for work, practice expense, and malpractice are each adjusted by that locality's GPCI values before being multiplied by the national conversion factor, so areas with higher relative costs typically show higher allowed amounts.

Why are the non-facility and facility amounts the same here?

When the practice-expense RVU is identical in both settings, as shown in the inputs for this code, the calculated allowed amount is the same regardless of site of service.

Does this amount reflect what the patient will pay?

No. It represents the Medicare-allowed amount before the standard 80/20 split; actual patient responsibility depends on deductible status, secondary coverage, and any applicable modifiers.

Can this number change during the year?

CMS can issue mid-year corrections, and annual updates to RVUs, GPCIs, or the conversion factor take effect at the start of each calendar year, so the estimate should be reverified periodically.

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Estimated Medicare Physician Fee Schedule amount. Medicare generally pays 80% after the deductible; actual amounts vary by locality, modifiers, sequestration, and annual updates. Verify with your MAC.