ICD-10-CM 2026 · Effective October 1, 2025

ICD-10 K21.00

Billable / Specific

Gastro-esophageal reflux disease with esophagitis, without bleeding

K21
Block
1
Synonyms
333
LCDs
18
Payer Policies
5
Linked CPTs

About ICD-10-CM K21.00

ICD-10-CM code K21.00 represents Gastro-esophageal reflux disease with esophagitis, without bleeding. This is a billable/specific code in the Digestive System chapter (block K21). The 2026 edition of ICD-10-CM K21.00 became effective on October 1, 2025.

Inclusion Terms / Approximate Synonyms

Clinical terms and conditions classified under K21.00. Per CMS ICD-10-CM Tabular 2026.

  • Reflux esophagitis

Medicare LCD Coverage for K21.00

Local Coverage Determinations (LCDs) from CMS MACs that list K21.00 as a covered diagnosis.

333 LCDs

Showing top 10 of 333 total . Click a CPT for full coverage scope.

CMS LCD: Billing and Coding: CT of the Abdomen and Pelvis
Article ID: 56421, Effective: 2025-11-01 00:00:00, 5389 covered, 0 non-covered
CPT 74170 →
CMS LCD: Billing and Coding: CT of the Abdomen and Pelvis
Article ID: 56421, Effective: 2025-11-01 00:00:00, 5389 covered, 0 non-covered
CPT 74177 →
CMS LCD: Billing and Coding: CT of the Abdomen and Pelvis
Article ID: 56421, Effective: 2025-11-01 00:00:00, 5389 covered, 0 non-covered
CPT 74160 →
CMS LCD: Billing and Coding: CT of the Abdomen and Pelvis
Article ID: 56421, Effective: 2025-11-01 00:00:00, 5389 covered, 0 non-covered
CPT 74178 →
CMS LCD: Billing and Coding: CT of the Abdomen and Pelvis
Article ID: 56421, Effective: 2025-11-01 00:00:00, 5389 covered, 0 non-covered
CPT 74150 →
CMS LCD: Billing and Coding: CT of the Abdomen and Pelvis
Article ID: 56421, Effective: 2025-11-01 00:00:00, 5389 covered, 0 non-covered
CPT 72194 →
CMS LCD: Billing and Coding: CT of the Abdomen and Pelvis
Article ID: 56421, Effective: 2025-11-01 00:00:00, 5389 covered, 0 non-covered
CPT 74176 →
CMS LCD: Billing and Coding: CT of the Abdomen and Pelvis
Article ID: 56421, Effective: 2025-11-01 00:00:00, 5389 covered, 0 non-covered
CPT 72192 →
CMS LCD: Billing and Coding: CT of the Abdomen and Pelvis
Article ID: 56421, Effective: 2025-11-01 00:00:00, 5389 covered, 0 non-covered
CPT 72193 →
CMS LCD: Billing and Coding: Endoscopic Treatment of GERD
Article ID: 56395, Effective: 2023-10-01 00:00:00, 3 covered, 1 non-covered
CPT 49999 →

Commercial Payer Coverage

Coverage policies from major commercial payers referencing K21.00.

18 policies

5 Medicare

Billing and Coding: Upper Gastrointestinal Endoscopy and Visualization
Policy ID: ART-56389
Billing and Coding: Endoscopic Treatment of GERD
Policy ID: ART-56395
Billing and Coding: CT of the Abdomen and Pelvis
Policy ID: ART-56421
Billing and Coding: Bariatric Surgical Management of Morbid Obesity
Policy ID: ART-56422
Billing and Coding: Swallowing Studies for Dysphagia
Policy ID: ART-56621

4 Aetna

Gastroesophageal Reflux Disease (GERD)
Policy ID: CPB-0213
Fiberoptic Endoscopic Evaluation of Swallowing (FEES)/Fiberoptic Endoscopic Evaluation of Swallowing with Sensory Testing (FEESST) and Laryngopharyngeal Endoscopic Esthesiometer (LPEER)
Policy ID: CPB-0248
Gastrointestinal Manometry
Policy ID: CPB-0616
Esophageal and Airway pH Monitoring
Policy ID: CPB-0667

CPT Codes Commonly Billed with K21.00

Procedures frequently paired with this diagnosis based on PayerReady's Dx↔Px linkage data.

5 linkages
  • 43284 CMS LCD: Billing and Coding: Lower Esophageal Magnetic Sphincter Augmentation CMS LCD
  • 43285 CMS LCD: Billing and Coding: Lower Esophageal Magnetic Sphincter Augmentation CMS LCD
  • 43257 CMS LCD: Billing and Coding: Stretta Procedure CMS LCD
  • 43999 CMS LCD: Billing and Coding: Select Minimally Invasive GERD Procedures CMS LCD
  • 49999 CMS LCD: Billing and Coding: Select Minimally Invasive GERD Procedures CMS LCD

ICD-10 K21.00, Billing FAQ

Is ICD-10 code K21.00 billable? +

Yes, K21.00 is a billable ICD-10-CM code that can appear as a primary or secondary diagnosis on claims.

What other names or terms map to K21.00? +

ICD-10 K21.00 includes: Reflux esophagitis.

What CPT codes are commonly billed with K21.00? +

Procedures frequently paired with K21.00 include: 43284, 43285, 43257, 43999, 49999.

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Reviewed by the PayerReady Medical Coding Team

Verified against the CMS 2026 code set on May 31, 2026.

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