2026 ICD-10-CM Diagnosis Code E10.621Type 1 diabetes mellitus with foot ulcer
ICD-10-CM Codes›E00–E89›E08-E13›E10
- Billable — Valid for Submission
- Risk Adjusts — HCC 37
- Chronic Condition
E10.621 is a billable ICD-10-CM diagnosis code for type 1 diabetes mellitus with foot ulcer. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 8, 10, 19, 637 through 639. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Diabetes mellitus with complication; Diabetes mellitus, Type 1; and Pressure ulcer of skin.
For Medicare Advantage risk adjustment, E10.621 maps to CMS-HCC Category 37 (Diabetes with Chronic Complications) under the V28 model, adding a risk factor of about 0.166 for a community, non-dual, aged beneficiary in payment year 2026.
Code Identity
Code Classification
Quality Payment Program MeasuresBilling
Medicare quality measures that can apply when E10.621 is part of the patient record.
Diabetes: Hemoglobin A1c (HbA1c) Poor Control (>9%)
High Priority: YES
Measure Type: Intermediateoutcome
Submission Methods: Claims, Electronic Health Record, Cms Web Interface, Registry
Description: Percentage of patients 18-75 years of age with diabetes who had hemoglobin A1c > 9.0% during the measurement period.
Medicare Risk Adjustment (HCC)Billing
E10.621 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 2026.
Source: CMS Payment Year 2026 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.
- Diabetic foot
- Skin ulcer due to diabetes mellitus
- Skin ulcer of toe due to diabetes mellitus type 1
- Ulcer of foot due to type 1 diabetes mellitus
- Ulcer of forefoot due to type 1 diabetes mellitus
- Ulcer of heel due to diabetes mellitus
- Ulcer of heel due to type 1 diabetes mellitus
- Ulcer of lower limb due to type 1 diabetes mellitus
- Ulcer of midfoot due to diabetes mellitus
- Ulcer of midfoot due to type 1 diabetes mellitus
Coding GuidelinesGuidance
The diabetes mellitus codes are combination codes that include the type of diabetes mellitus, the body system affected, and the complications affecting that body system. As many codes within a particular category as are necessary to describe all of the complications of the disease may be used. They should be sequenced based on the reason for a particular encounter. Assign as many codes from categories E08 - E13 as needed to identify all of the associated conditions that the patient has.
The age of a patient is not the sole determining factor, though most type 1 diabetics develop the condition before reaching puberty. For this reason type 1 diabetes mellitus is also referred to as juvenile diabetes.
Source: ICD-10-CM Official Guidelines for Coding and Reporting, FY 2026, published by CMS and the National Center for Health Statistics.
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
Use Additional Code
The “use additional code” indicates that a secondary code could be used to further specify the patient’s condition. This note is not mandatory and is only used if enough information is available to assign an additional 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.
Clinical InformationClinical
Diabetic Foot
common foot problems in persons with diabetes mellitus, caused by any combination of factors such as diabetic neuropathies; peripheral vascular diseases; and infection. with the loss of sensation and poor circulation, injuries and infections often lead to severe foot ulceration, gangrene and amputation, surgical.
Patient EducationClinical
Diabetes Type 1
Diabetes means your blood glucose, or blood sugar, levels are too high. With type 1 diabetes, your pancreas does not make insulin. Insulin is a hormone that helps glucose get into your cells to give them energy. Without insulin, too much glucose stays in your blood.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert E10.621 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About E10.621Overview
What is the ICD-10 code for type 1 diabetes mellitus with foot ulcer?
The ICD-10-CM code for type 1 diabetes mellitus with foot ulcer is E10.621 (sometimes written as E10621). It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
Is E10.621 (Type 1 diabetes mellitus with skin complications) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report type 1 diabetes mellitus with foot ulcer on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does E10.621 group to?
When type 1 diabetes mellitus with foot ulcer is the principal diagnosis on an inpatient stay, it groups to MS-DRG 8, 10, 19, 637, 638, 639, with relative weights from 0.6212 to 6.6272 depending on complications. Higher weights mean higher Medicare reimbursement.
What is the ICD-9 equivalent of E10.621?
Under the General Equivalence Mappings, type 1 diabetes mellitus with foot ulcer converts to ICD-9-CM 250.81 (DMI oth nt st uncntrld). The mapping is approximate, so confirm the match fits the documentation.
What HCC is E10.621?
E10.621 (type 1 diabetes mellitus with foot ulcer) maps to CMS-HCC Category 37 (Diabetes with Chronic Complications), commonly written as HCC 37, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2026. It mapped to HCC 18 under the retired V24 model. It also maps in the PACE (CMS-HCC V22), ESRD (V21), and ESRD (V24) models. In the Part D prescription drug model it maps to RxHCC 311.
Does E10.621 risk-adjust for Medicare Advantage payment?
Yes. When documented and reported on a Medicare Advantage encounter, E10.621 adds a risk adjustment factor of about 0.166 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.166 to 0.280 depending on the payment segment). A more severe related category (HCC 35 and HCC 36) supersedes it when both are reported. See the full factor table on the HCC 37 category page.
