FeeBase
Log inGet started
Menu

CPT code 91038: Esophageal impedance, more than one hour2026 Medicare rate & RVUs in Connecticut

Reports prolonged catheter-based esophageal impedance monitoring to evaluate reflux episodes and their relationship to symptoms during a recording lasting more than one hour.

CMS RVU26DEffective Oct 1, 2026One payment locality3.6K Medicare services in 2024

In Connecticut, Medicare pays $478.50 for 91038 in the office.

$478.50Office (non-facility)
Not available in this settingHospital or facility
+7.3%vs the national office rate ($445.90)

Check a contract rate as a % of Medicare · 91038 nationwide

Medicare allowed amount for participating (non-QP) physicians, before deductible, coinsurance and claim adjustments. Not a patient’s bill or a hospital charge.

We’ll open 91038 for the payment locality that covers the ZIP.

On this page 11 sections
  1. Rate in Connecticut
  2. What 91038 covers
  3. Compared with other areas
  4. Rate map
  5. How it’s calculated
  6. Payment rules
  7. Related codes
  8. Rate history
  9. Where it applies
  10. Billing questions
  11. Sources

What 91038 covers

A thin catheter with impedance sensors is passed through the nose into the esophagus to record movement of swallowed material and reflux over a prolonged period. The test can help evaluate persistent heartburn, regurgitation, or other suspected reflux symptoms, including symptoms that continue during acid-suppressing treatment. It is typically performed in a gastroenterology or motility laboratory, with a physician interpreting the recording and reporting the findings.

Select this service for impedance monitoring lasting more than one hour, rather than the shorter-duration service. Documentation should support catheter placement, the recording period, analysis, and interpretation. CMS recognizes professional and technical components: modifier 26 identifies interpretation, modifier TC identifies equipment and staff, and no component modifier represents the global service. The 0-day global period includes same-day preoperative and postoperative care. Modifier 50 is inappropriate. Assistant-at-surgery payment requires documented medical necessity; 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.

How Connecticut compares for 91038

Across 109 of 109 payment localities, the office rate for 91038 runs from $387.29 in Arkansas to $628.37 in San Benito County, CA. Connecticut pays $478.50. The RVUs are the same everywhere; the geographic indexes change the dollars.

91038 in Connecticut vs other payment areas
  1. Connecticut · this page$478.50
  2. Los Angeles, CA · California$520.90+$42.40
  3. Washington, DC area · District of Columbia$520.54+$42.04
  4. Miami, FL · Florida$466.65−$11.85
  5. Chicago, IL · Illinois$451.65−$26.85
  6. Manhattan, NY · New York$515.67+$37.17
  7. Alaska · Alaska$489.49+$10.99

Other areas in Connecticut first, then benchmark localities. Bars start at $0.

Every other payment area

91038 in every other Medicare payment locality
Payment localityOfficeFacility
AlabamaAlabama$393.93—
ArkansasArkansas$387.29—
ArizonaArizona$432.92—
Bakersfield, CACalifornia$484.58—
Chico, CACalifornia$484.31—
El Centro, CACalifornia$484.32—
Fresno, CACalifornia$484.31—
Hanford, CACalifornia$484.31—

91038 rates by state

Office rate range in each state. Select a state to see its payment localities.

MEWIVTNHMTNDMNMINYMARIWAIDWYSDIAILINOHPANJCTORNVUTCONEMOKYWVVAMDDECAAZNMKSOKARTNNCSCDCTXLAMSALGAFLAKHI

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.

$387.29

$556.34

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

View every state and territory as a table
91038 office rate range by state
State / territoryOffice rate rangeLocalities
AK$489.491
AL$393.931
AR$387.291
AZ$432.921
CA$484.31–$628.3729
CO$471.771
CT$478.501
DC$520.541
DE$440.941
FL$429.36–$466.653
GA$402.51–$453.052
GU$500.471
HI$500.471
IA$409.741
ID$411.971
IL$412.04–$459.204
IN$414.851
KS$405.551
KY$400.551
LA$399.04–$422.282
MA$467.49–$525.972
MD$450.93–$520.543
ME$412.37–$441.262
MI$410.88–$433.512
MN$455.811
MO$389.74–$426.403
MS$388.701
MT$445.901
NC$417.701
ND$444.311
NE$412.941
NH$462.231
NJ$485.03–$513.442
NM$412.701
NV$445.861
NY$424.78–$527.375
OH$410.561
OK$401.811
OR$443.48–$490.932
PA$412.42–$463.752
PR$450.331
RI$459.731
SC$414.611
SD$444.131
TN$407.671
TX$409.13–$469.258
UT$421.241
VA$438.21–$520.542
VI$450.331
VT$440.521
WA$467.28–$539.522
WI$426.981
WV$393.801
WY$445.211

See 91038 in every payment locality

How the 91038 rate is calculated

Each of 91038’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 · 91038

RVUs × geographic indexes × conversion factor

Office or facility?

Work1.10

1.10 RVUs× 1.000 GPCI

Practice expense12.17

12.17 RVUs× 1.000 GPCI

Malpractice0.08

0.08 RVUs× 1.000 GPCI

Adjusted RVUs

13.3500

Conversion factor

$33.4009

Medicare rate

$445.90

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

The exact Connecticut inputs and CMS source lines

PPRRVU2026_Oct_nonQPP.csv

11,612

Code
91038
Physician work
1.10
Practice expense
12.17
Malpractice
0.08

GPCI2026.csv

38

Locality
Connecticut
Physician work
1.020
Practice expense
1.077
Malpractice
1.210
Office calculation for 91038 in Connecticut
ComponentRVULocality factorAdjusted
Physician work1.10× 1.0201.1220
Practice expense12.17× 1.07713.1071
Malpractice0.08× 1.2100.0968
Total RVUs14.3259
Conversion factor× 33.4009

Office rate, Connecticut$478.50

Office: (1.1 × 1.02 + 12.17 × 1.077 + 0.08 × 1.21) × $33.4009 = $478.50

Open 91038 in the RVU calculator

Payment rules and modifiers for 91038

The CMS indicators that decide how 91038 is paid alongside other services.

CMS payment indicators · 91038

Esophageal impedance, more than one hour

RuleCMS valueWhat it means
Global period000Same-day global: pre- and post-op care on the day of the procedure is included.
Multiple procedures0No multiple-procedure reduction.
Bilateral (modifier 50)0The 150% bilateral adjustment doesn’t apply.
Assistant at surgery (80/81/82/AS)0Not paid without supporting documentation.
Co-surgeons (62)0Not permitted.
Team surgery (66)0Not permitted.
Professional/technical1Diagnostic test with separate professional (26) and technical (TC) components.

What modifiers do to the payment

Modifier 26 · payment effect

With and without the modifier

91038 without 26 · national office

$445.90

Esophageal impedance, more than one hour

91038-26 · Professional component

$59.79

Pays only the interpretation and report.

When to use modifier 26

Codes related to 91038

Related codes aren’t interchangeable: bill the code that matches the service performed.

Codes related to 91038
CodeHow it relatesOffice range, Connecticut
Same family
91037Esophageal impedance, one hour or lessShorter-duration esophageal impedance monitoring.$200.31
Used instead
91034Reflux monitoring, nasal catheter pH testCatheter-based reflux monitoring focused on esophageal pH rather than impedance.$216.54
91035Reflux testing, mucosa-attached telemetry electrodeWireless esophageal reflux monitoring using an attached pH electrode.$538.75

How 91038 has changed in Connecticut

91038 · Office / nonfacility

$478.50

Effective 2026-10-01

The base rate is $71.72 higher than on 2025-10-01, moving from $406.78 to $478.50 (17.6%).

It is unchanged from the immediately preceding available release, effective 2026-07-01.

Base rate by release · bars start at $0 · select a bar to compare

One bar per available release, ordered by effective date. Missing rates remain gaps. These comparisons hold the code, setting and locality identifiers constant; they do not isolate which policy or input caused a change.

What changed, release by release

  1. January 1, 2026

    RVU26A

    $406.78changed to$478.50

    • Conversion factor 32.3465 changed to 33.4009
    • Practice expense RVU 10.43 changed to 12.17
    • Malpractice RVU 0.06 changed to 0.08
    • Work GPCI 1.022 changed to 1.020
    • Practice expense GPCI 1.091 changed to 1.077
    • Malpractice GPCI 1.207 changed to 1.210

    Held through RVU26B, RVU26C, RVU26D.

  2. January 1, 2025

    RVU25A

    $436.45changed to$406.78

    • Conversion factor 33.2875 changed to 32.3465
    • Practice expense RVU 10.91 changed to 10.43
    • Malpractice RVU 0.07 changed to 0.06

    Held through RVU25B, RVU25C, RVU25D.

  3. March 9, 2024

    RVU24AR

    $429.33changed to$436.45

    • Conversion factor 32.7442 changed to 33.2875

    Held through RVU24B, RVU24C, RVU24D.

  4. January 1, 2024

    RVU24A

    $455.08changed to$429.33

    • Conversion factor 33.8872 changed to 32.7442
    • Practice expense RVU 11.10 changed to 10.91
    • Malpractice RVU 0.06 changed to 0.07
    • Work GPCI 1.030 changed to 1.022
    • Practice expense GPCI 1.102 changed to 1.091
    • Malpractice GPCI 1.070 changed to 1.207

  5. January 1, 2023

    RVU23A

    $486.68changed to$455.08

    • Conversion factor 34.6062 changed to 33.8872
    • Practice expense RVU 11.55 changed to 11.10
    • Work GPCI 1.037 changed to 1.030
    • Practice expense GPCI 1.114 changed to 1.102
    • Malpractice GPCI 0.934 changed to 1.070

    Held through RVU23B, RVU23C, RVU23D.

  6. January 1, 2022

    RVU22A

    $510.99changed to$486.68

    • Conversion factor 34.8931 changed to 34.6062
    • Practice expense RVU 12.08 changed to 11.55
    • Malpractice RVU 0.05 changed to 0.06

    Held through RVU22B, RVU22C, RVU22D.

  7. January 1, 2021

    RVU21A

    $496.71changed to$510.99

    • Conversion factor 36.0896 changed to 34.8931
    • Practice expense RVU 11.29 changed to 12.08
    • Malpractice RVU 0.06 changed to 0.05
    • Work GPCI 1.029 changed to 1.037
    • Practice expense GPCI 1.113 changed to 1.114
    • Malpractice GPCI 1.094 changed to 0.934

    Held through RVU21B, RVU21C, RVU21D.

  8. January 1, 2020

    RVU20A

    $500.05changed to$496.71

    • Conversion factor 36.0391 changed to 36.0896
    • Practice expense RVU 11.40 changed to 11.29
    • Work GPCI 1.021 changed to 1.029
    • Practice expense GPCI 1.112 changed to 1.113
    • Malpractice GPCI 1.255 changed to 1.094

    Held through RVU20B, RVU20C, RVU20D.

  9. January 1, 2019

    RVU19A

    $507.56changed to$500.05

    • Conversion factor 35.9996 changed to 36.0391
    • Practice expense RVU 11.59 changed to 11.40
    • Malpractice RVU 0.07 changed to 0.06

    Held through RVU19B, RVU19C, RVU19D.

  10. January 1, 2018

    RVU18AR1

    $503.72changed to$507.56

    • Conversion factor 35.8887 changed to 35.9996
    • Practice expense RVU 11.48 changed to 11.59
    • Work GPCI 1.023 changed to 1.021
    • Practice expense GPCI 1.117 changed to 1.112
    • Malpractice GPCI 1.244 changed to 1.255

    Held through RVU18B, RVU18C, RVU18D.

  11. January 1, 2017

    RVU17A

    $504.59changed to$503.72

    • Conversion factor 35.8043 changed to 35.8887
    • Practice expense RVU 11.49 changed to 11.48
    • Work GPCI 1.024 changed to 1.023
    • Practice expense GPCI 1.121 changed to 1.117
    • Malpractice GPCI 1.232 changed to 1.244

    Held through RVU17B, RVU17C, RVU17D.

  12. January 1, 2016

    RVU16A

    $515.79changed to$504.59

    • Conversion factor 35.9335 changed to 35.8043
    • Practice expense RVU 11.69 changed to 11.49
    • Malpractice RVU 0.10 changed to 0.07

    Held through RVU16B, RVU16C, RVU16D.

  13. July 1, 2015

    RVU15C

    $513.23changed to$515.79

    • Conversion factor 35.7547 changed to 35.9335

    Held through RVU15D.

  14. January 1, 2015

    RVU15A

    $505.55changed to$513.23

    • Conversion factor 35.8228 changed to 35.7547
    • Practice expense RVU 11.57 changed to 11.69
    • Malpractice RVU 0.06 changed to 0.10
    • Practice expense GPCI 1.116 changed to 1.121
    • Malpractice GPCI 1.234 changed to 1.232

    Held through RVU15B.

  15. January 1, 2014

    RVU14A

    $544.64changed to$505.55

    • Conversion factor 34.0230 changed to 35.8228
    • Practice expense RVU 13.34 changed to 11.57
    • Practice expense GPCI 1.110 changed to 1.116
    • Malpractice GPCI 1.235 changed to 1.234

    Held through RVU14B, RVU14C, RVU14D.

  16. January 1, 2013

    RVU13AR

    Earliest loaded release: $544.64

    Held through RVU13B, RVU13C, RVU13D.

Rates in every CMS release
Effective fromOfficeFacilityCMS release
2026-10-01$478.50Not available in this settingRVU26D
2026-07-01$478.50Not available in this settingRVU26C
2026-04-01$478.50Not available in this settingRVU26B
2026-01-01$478.50Not available in this settingRVU26A
2025-10-01$406.78Not available in this settingRVU25D
2025-07-01$406.78Not available in this settingRVU25C
2025-04-01$406.78Not available in this settingRVU25B
2025-01-01$406.78Not available in this settingRVU25A
2024-10-01$436.45Not available in this settingRVU24D
2024-07-01$436.45Not available in this settingRVU24C
2024-04-01$436.45Not available in this settingRVU24B
2024-03-09$436.45Not available in this settingRVU24AR
2024-01-01$429.33Not available in this settingRVU24A
2023-10-01$455.08Not available in this settingRVU23D
2023-07-01$455.08Not available in this settingRVU23C
2023-04-01$455.08Not available in this settingRVU23B
2023-01-01$455.08Not available in this settingRVU23A
2022-10-01$486.68Not available in this settingRVU22D
2022-07-01$486.68Not available in this settingRVU22C
2022-04-01$486.68Not available in this settingRVU22B
2022-01-01$486.68Not available in this settingRVU22A
2021-10-01$510.99Not available in this settingRVU21D
2021-07-01$510.99Not available in this settingRVU21C
2021-04-01$510.99Not available in this settingRVU21B
2021-01-01$510.99Not available in this settingRVU21A
2020-10-01$496.71Not available in this settingRVU20D
2020-07-01$496.71Not available in this settingRVU20C
2020-04-01$496.71Not available in this settingRVU20B
2020-01-01$496.71Not available in this settingRVU20A
2019-10-01$500.05Not available in this settingRVU19D
2019-07-01$500.05Not available in this settingRVU19C
2019-04-01$500.05Not available in this settingRVU19B
2019-01-01$500.05Not available in this settingRVU19A
2018-10-01$507.56Not available in this settingRVU18D
2018-07-01$507.56Not available in this settingRVU18C
2018-04-01$507.56Not available in this settingRVU18B
2018-01-01$507.56Not available in this settingRVU18AR1
2017-10-01$503.72Not available in this settingRVU17D
2017-07-01$503.72Not available in this settingRVU17C
2017-04-01$503.72Not available in this settingRVU17B
2017-01-01$503.72Not available in this settingRVU17A
2016-10-01$504.59Not available in this settingRVU16D
2016-07-01$504.59Not available in this settingRVU16C
2016-04-01$504.59Not available in this settingRVU16B
2016-01-01$504.59Not available in this settingRVU16A
2015-10-01$515.79Not available in this settingRVU15D
2015-07-01$515.79Not available in this settingRVU15C
2015-04-01$513.23Not available in this settingRVU15B
2015-01-01$513.23Not available in this settingRVU15A
2014-10-01$505.55Not available in this settingRVU14D
2014-07-01$505.55Not available in this settingRVU14C
2014-04-01$505.55Not available in this settingRVU14B
2014-01-01$505.55Not available in this settingRVU14A
2013-10-01$544.64Not available in this settingRVU13D
2013-07-01$544.64Not available in this settingRVU13C
2013-04-01$544.64Not available in this settingRVU13B
2013-01-01$544.64Not available in this settingRVU13AR

Price 91038 for an earlier date of service

Where the Connecticut rate applies

Connecticut is a Medicare payment area, not a city. Our Census mapping connects it to 215 cities and communities in Connecticut. Some span more than one payment area; confirm with the service ZIP.

  • Ansonia
  • Ball Pond
  • Baltic
  • Bantam
  • Bethel
  • Bethlehem Village
  • Bigelow Corners
  • Blue Hills

Browse all communities in Connecticut

91038 billing questions

When should this code be selected instead of 91037?

Use this code when the impedance recording lasts more than one hour. Code 91037 is for the shorter-duration impedance test.

Can the professional and technical services be billed separately?

Yes. Modifier 26 identifies the professional interpretation, and modifier TC identifies the technical service, including equipment and staff. Without either modifier, the claim represents the global service.

What documentation supports the service?

Document catheter placement, the duration of the impedance recording, and the analysis and interpretation. The record should also support the clinical reason for evaluating reflux or related symptoms.

Is modifier 50 appropriate for this test?

No. CMS identifies bilateral adjustment as inappropriate for this service.

How does this differ from catheter-based pH monitoring?

Impedance monitoring evaluates movement of material through the esophagus, including reflux episodes. Code 91034 describes catheter-based pH monitoring, which measures esophageal acidity.

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 91038PPRRVU2026_Oct_nonQPP.csv, line 11,612 (RVU26D)
Geographic factors for ConnecticutGPCI2026.csv, line 38 (RVU26D)

Open CMS sourceHow we calculate rates

Did this answer your question about what 91038 pays in Connecticut?

Tell us what you were actually trying to work out. We’ll answer you directly, or build the page that does.

Fee sheets · Coming soon

Put 91038 and the rest of your codes on one sheet

Your codes at your locality, with payer contracts beside Medicare.

Join the waitlist