2027 ICD-10-CM Diagnosis Code T31.81Burns involving 80-89% of body surface with 10-19% third degree burns
ICD-10-CM Codes›S00–T88›T30-T32›T31
- Billable — Valid for Submission
- MCC — Major Complication or Comorbidity
- Risk Adjusts — HCC 385
- Not Chronic
T31.81 is a billable ICD-10-CM diagnosis code for burns involving 80-89% of body surface with 10-19% third degree burns. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 927, 933. As a secondary diagnosis, it counts as a major complication or comorbidity (MCC) and places an inpatient stay in the highest severity level of its MS-DRG family. It does not count, however, when the principal diagnosis is one of 110 closely related codes. Coders also document this condition as burn any degree involving 80-89 percent of body surface. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Burn and corrosion, initial encounter.
For Medicare Advantage risk adjustment, T31.81 maps to CMS-HCC Category 385 (Severe Skin Burn or Condition) under the V28 model, adding a risk factor of about 1.291 for a community, non-dual, aged beneficiary in payment year 2027.
Code Identity
Code Classification
Medicare Risk Adjustment (HCC)Billing
T31.81 maps to a payment category in the CMS-HCC model used to risk-adjust Medicare Advantage payments. Weights are the published community factors for payment year 2027.
Source: CMS Payment Year 2027 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Burn any degree involving 80-89 percent of body surface
- Burn involving 80-89 percent of body surface, with 10-19 percent of body surface with full thickness burn
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.
Assign codes from category T31, Burns classified according to extent of body surface involved, or T32, Corrosions classified according to extent of body surface involved, when the site of the burn is not specified or when there is a need for additional data. It is advisable to use category T31 as additional coding when needed to provide data for evaluating burn mortality, such as that needed by burn units. It is also advisable to use category T31 as an additional code for reporting purposes when there is mention of a third-degree burn involving 20 percent or more of the body surface.
Categories T31 and T32 are based on the classic "rule of nines" in estimating body surface involved: head and neck are assigned nine percent, each arm nine percent, each leg 18 percent, the anterior trunk 18 percent, posterior trunk 18 percent, and genitalia one percent. Providers may change these percentage assignments where necessary to accommodate infants and children who have proportionately larger heads than adults, and patients who have large buttocks, thighs, or abdomen that involve burns.
Source: ICD-10-CM Official Guidelines for Coding and Reporting, FY 2027, published by CMS and the National Center for Health Statistics.
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to T31.81: its own notes plus those printed at T31, block T20-T32, and Chapter 19. A note printed at a category, block or chapter applies to every code under it.
Includes
Further defines, or gives examples of, the content of the category.
- burns (thermal) from electrical heating appliances
- burns (thermal) from electricity
- burns (thermal) from flame
- burns (thermal) from friction
- burns (thermal) from hot air and hot gases
- burns (thermal) from hot objects
- burns (thermal) from lightning
- burns (thermal) from radiation
- chemical burn [corrosion] (external) (internal)
- scalds
Excludes2
Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.
Use Additional Code
Add a second code, after this one, to fully describe the condition.
- code to identify any retained foreign body, if applicable (Z18.-)
Notes
General instructions on how these codes are used.
- Use secondary code(s) from Chapter 20, External causes of morbidity, to indicate cause of injury. Codes within the T section that include the external cause do not require an additional external cause code
- The chapter uses the S-section for coding different types of injuries related to single body regions and the T-section to cover injuries to unspecified body regions as well as poisoning and certain other consequences of external causes.
Source: CMS ICD-10-CM Tabular List. How to read instructional notes.
Referenced in Other NotesGuidance
Instructional notes printed at other codes that name T31.81, its category, or a range that includes it.
Use Additional Code 1
These codes say to use an additional code from the note, and T31.81 is one of the codes named.
- Block T20-T25 Burns and corrosions of external body surface, specified by sitecode from category T31 or T32 to identify extent of body surface involved names T31, which includes this code
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
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 T31.81 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About T31.81Overview
What is the ICD-10 code for burns involving 80-89% of body surface with 10-19% third degree burns?
The ICD-10-CM code for burns involving 80-89% of body surface with 10-19% third degree burns is T31.81 (sometimes written as T3181). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
Is T31.81 (Burns involving 80-89% of body surface) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report burns involving 80-89% of body surface with 10-19% third degree burns on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What MS-DRG does T31.81 group to?
When burns involving 80-89% of body surface with 10-19% third degree burns is the principal diagnosis on an inpatient stay, it groups to MS-DRG 927, 933, with relative weights from 2.3939 to 27.8336 depending on complications. Higher weights mean higher Medicare reimbursement.
Is T31.81 a CC or MCC?
CMS lists T31.81 as an MCC (major complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it places the inpatient stay in the highest-weighted DRG of its severity family. It does not count when the principal diagnosis is one of the 110 closely related codes in its exclusion list.
What is the ICD-9 equivalent of T31.81?
Under the General Equivalence Mappings, burns involving 80-89% of body surface with 10-19% third degree burns converts to ICD-9-CM 948.81 (80-89% bdy brn/10-19% 3d). The mapping is approximate, so confirm the match fits the documentation.
What HCC is T31.81?
T31.81 (burns involving 80-89% of body surface with 10-19% third degree burns) maps to CMS-HCC Category 385 (Severe Skin Burn or Condition), commonly written as HCC 385, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2027. It mapped to HCC 162 under the retired V24 model. It also maps in the PACE (CMS-HCC V22), ESRD (V21), and ESRD (V24) models. It does not map to any RxHCC in the Part D prescription drug model.
Does T31.81 risk-adjust for Medicare Advantage payment?
Yes. When documented and reported on a Medicare Advantage encounter, T31.81 adds a risk adjustment factor of about 1.291 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.000 to 2.362 depending on the payment segment). HCC 385 sits at the top of its hierarchy, so no other condition category supersedes it. See the full factor table on the HCC 385 category page.
