2026 ICD-10-CM Diagnosis Code T28.0XXSBurn of mouth and pharynx, sequela
T28.0XXS is a billable ICD-10-CM diagnosis code for burn of mouth and pharynx, sequela. The 7th character S marks it as a sequela code, which reports a problem that remains after the original condition has resolved. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 604 through 605. The code is exempt from POA reporting. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Injury, sequela.
Code Identity
Code Classification
Present on Admission (POA)Billing
T28.0XXS is exempt from POA reporting on inpatient claims to general acute care hospitals. Review other POA exempt codes.
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Abrasion and/or friction burn of gum with infection
- Abrasion and/or friction burn of gum without infection
- Abrasion and/or friction burn of head and/or neck without infection
- Burn erythema of buccal mucosa
- Burn erythema of floor of mouth
- Burn erythema of hard palate
- Burn erythema of mandibular attached gingiva
- Burn erythema of mandibular vestibule
- Burn erythema of maxillary attached gingiva
- Burn erythema of maxillary vestibule
- Burn erythema of oropharynx
- Burn erythema of soft palate
- Burn erythema of tongue
- Burn erythema of tonsillar area
- Burn of buccal mucosa
- Burn of circumoral region
- Burn of floor of mouth
- Burn of gum
- Burn of hard palate
- Burn of labial mucosa
- Burn of larynx
- Burn of larynx and/or trachea
- Burn of mandibular attached gingiva
- Burn of mandibular vestibule
- Burn of maxillary attached gingiva
- Burn of maxillary vestibule
- Burn of mouth
- Burn of mouth and pharynx
- Burn of mucous membrane of mouth
- Burn of oral cavity
- Burn of oropharynx
- Burn of pharynx
- Burn of soft palate
- Burn of throat
- Burn of tongue
- Burn of tonsillar area
- Full thickness burn of buccal mucosa
- Full thickness burn of cheek
- Full thickness burn of tongue
- Gingival disease due to thermal injury
- Oral ulceration due to thermal burn
- Second degree burn of buccal mucosa
- Second degree burn of floor of mouth
- Second degree burn of hard palate
- Second degree burn of mandibular attached gingiva
- Second degree burn of mandibular vestibule
- Second degree burn of maxillary attached gingiva
- Second degree burn of maxillary vestibule
- Second degree burn of oropharynx
- Second degree burn of soft palate
- Second degree burn of tongue
- Second degree burn of tonsillar area
- Superficial injury of gum with infection
- Third degree burn of floor of mouth
- Third degree burn of hard palate
- Third degree burn of mandibular attached gingiva
- Third degree burn of mandibular vestibule
- Third degree burn of maxillary attached gingiva
- Third degree burn of maxillary vestibule
- Third degree burn of oropharynx
- Third degree burn of soft palate
- Third degree burn of tonsillar area
Coding GuidelinesGuidance
The ICD-10-CM makes a distinction between burns and corrosions. The burn codes are for thermal burns, except sunburns, that come from a heat source, such as a fire or hot appliance. The burn codes are also for burns resulting from electricity and radiation. Corrosions are burns due to chemicals. The guidelines are the same for burns and corrosions.
Sequence first the code that reflects the highest degree of burn when more than one burn is present.
- When the reason for the admission or encounter is for treatment of external multiple burns, sequence first the code that reflects the burn of the highest degree.
- When a patient has both internal and external burns, the circumstances of admission govern the selection of the principal diagnosis or first-listed diagnosis.
- When a patient is admitted for burn injuries and other related conditions such as smoke inhalation and/or respiratory failure, the circumstances of admission govern the selection of the principal or first-listed diagnosis.
Burns of the eye and internal organs (T26-T28) are classified by site, but not by degree.
Classify burns of the same local site (three-character category level, T20-T28) but of different degrees to the subcategory identifying the highest degree recorded in the diagnosis.
The appropriate 7th character is to be added to each code from block Burn and corrosion of other internal organs (T28). Use the following options for the applicable episode of care:
- A - initial encounter
- D - subsequent encounter
- S - sequela
Source: ICD-10-CM Official Guidelines for Coding and Reporting, FY 2026, published by CMS and the National Center for Health Statistics.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Burns
A burn is damage to your body's tissues caused by heat, chemicals, electricity, sunlight, or radiation. Scalds from hot liquids and steam, building fires and flammable liquids and gases are the most common causes of burns. Another kind is an inhalation injury, caused by breathing smoke.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert T28.0XXS to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About T28.0XXSOverview
Is T28.0XXS (Burn of mouth and pharynx) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report burn of mouth and pharynx, sequela on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What does the 7th character S in T28.0XXS mean?
The final character S makes this a sequela code: it reports a lingering problem that remains after the burn of mouth and pharynx itself has resolved, not the original event.
What MS-DRG does T28.0XXS group to?
When burn of mouth and pharynx, sequela is the principal diagnosis on an inpatient stay, it groups to MS-DRG 604, 605, with relative weights from 0.9160 to 1.4721 depending on complications. Higher weights mean higher Medicare reimbursement.
Is T28.0XXS exempt from POA reporting?
Yes. CMS lists this code among those exempt from present on admission reporting, so hospitals do not assign a POA indicator for burn of mouth and pharynx, sequela on inpatient claims.
What is the ICD-9 equivalent of T28.0XXS?
Under the General Equivalence Mappings, burn of mouth and pharynx, sequela converts to ICD-9-CM 906.8 (late effect of burns NEC). The mapping is approximate, so confirm the match fits the documentation.
Footnotes
[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.
