ICD-10 Code for Diabetes Type 2 (E11)
Complete Guide with Complications & Combinations
Blog Outline
- ICD-10 Code E11 For type 2 Diabetes Mellitus
- E11.65 – Type 2 Diabetes Mellitus With Hyperglycemia
- E11.2 Series – Diabetes With Kidney Complications
- E11.3 Series – Diabetes With Ophthalmic Complications
- E11.4 Series – Diabetes With Neurological Complications
- E11.5 Series – Diabetes With Circulatory Complications
- E11.6 Series – Skin & Ulcer Complications
- E11.8 – Type 2 Diabetes Mellitus With Unspecified Complications
- E11.9 – Type 2 Diabetes Without Complications (Extended Clarification)
- ICD-10 Combination Coding For Type 2 Diabetes
- Z79.4 & Z79.84 – Long-term Medication Use With Diabetes
- Pediatric Coding for type 2 Diabetes (E11 Series)
- Conclusion
- FAQs
ICD-10 Code for Type 2 Diabetes Mellitus (E11)
The ICD-10 code for Type 2 diabetes mellitus is E11. This category includes all patients diagnosed with Type 2 diabetes, whether the condition is controlled with diet, oral medications, or long-term insulin therapy.
In medical coding, the base code E11 is rarely used alone. Most cases require a more specific E11.x diagnosis code to reflect complications such as neuropathy, chronic kidney disease (CKD), retinopathy, or hyperglycemia.
- E11 = Type 2 diabetes mellitus (general category)
- E11.9 = Type 2 diabetes without complications
- E11.65 = Type 2 diabetes with hyperglycemia
- E11.42 = Type 2 diabetes with polyneuropathy
E11.9 ICD-10 Code – Type 2 Diabetes Mellitus Without Complications
What Does E11.9 Mean?
E11.9 is the ICD-10 code for Type 2 diabetes mellitus without complications. It is used when the provider documents diabetes but does not mention any associated conditions or organ damage.
Assign E11.9 when:
- The documentation states “Type 2 diabetes, stable” or “well-controlled”
- No complications such as neuropathy, CKD, or retinopathy are documented
- The visit is focused on routine diabetes management or follow-up
- The record is general or unclear, with no complication specified
According to ICD-10-CM guidelines, if the type of diabetes is not specified, it defaults to Type 2 diabetes, making E11.9 appropriate in many cases.
E11.9 represents:
- Type 2 diabetes without organ damage
- No documented hyperglycemia or complications
- Standard outpatient diabetes management
This is one of the most commonly used ICD-10 diagnosis codes in primary care and endocrinology. Accurate coding of E11.9 is essential – our internal medicine billing services help primary care providers ensure compliant coding, and optimize reimbursement for diabetes care.
Additional Codes to Use With E11.9
Even without complications, additional codes may be required:
- Z79.4 – Long-term use of insulin
- Z79.84 – Long-term use of oral antidiabetic drugs
- Z71.3 – Dietary counseling (if documented)
These codes help reflect the treatment plan and ongoing management of diabetes.
E11.65 ICD-10 Code for Type 2 Diabetes Mellitus With Hyperglycemia
E11.65 is the ICD-10 code for Type 2 diabetes mellitus with hyperglycemia. This code is used when a patient with Type 2 diabetes has elevated blood glucose levels beyond the normal range.
What Does E11.65 Mean?
E11.65 means:
- The patient has Type 2 diabetes
- AND the condition is associated with high blood sugar (hyperglycemia)
In ICD-10-CM coding, terms like:
- “poorly controlled diabetes”
- “uncontrolled diabetes”
- “elevated glucose levels”
are all interpreted as hyperglycemia, making E11.65 the correct diagnosis code in most cases.
E11.65 Description
E11.65 represents:
- Type 2 diabetes with persistent or clinically significant hyperglycemia
- Worsening glycemic control requiring treatment adjustment
- Diabetes with documented high glucose readings
This is one of the most commonly used ICD-10 diagnosis codes for uncontrolled Type 2 diabetes in outpatient and endocrinology settings.
When to Use E11.65
Assign E11.65 when:
- The provider documents hyperglycemia
- Notes include “poor glycemic control” or “uncontrolled diabetes”
- Blood glucose levels are consistently elevated
- Medication or insulin therapy is adjusted due to high sugar levels
- Steroid-induced hyperglycemia is linked to diabetes
E11.2 Series – Diabetes with Kidney Complications
1
E11.21 – Type 2 Diabetes Mellitus With Diabetic Nephropathy
E11.21 is assigned when the provider documents diabetic nephropathy, meaning kidney damage directly linked to diabetes. This code is used when notes include language such as:
Diabetic nephropathy
Diabetic kidney damage
Diabetic renal disease
Diabetic proteinuria or albuminuria
Key Coding Points:
No secondary CKD code is required unless the provider documents an actual CKD stage.
If the note only states “nephropathy” but doesn’t specify diabetic origin, query the provider for clarification.
If the provider confirms it is “diabetic nephropathy,” E11.21 is the correct code.
2
E11.22 – Type 2 Diabetes Mellitus With Chronic Kidney Disease (CKD)
Use E11.22 when the provider documents CKD caused by or associated with Type 2 diabetes. This requires two codes:
E11.22 – Diabetes with CKD
N18.x – CKD stage
N18.1–N18.9 (Stage 1–5 or unspecified)
N18.6 for ESRD
Important Documentation Notes
The provider must specify both “diabetes” and “CKD” or state a relationship (“diabetic CKD,” “diabetes with CKD,” etc.).
If the stage is not documented, use N18.9 (CKD unspecified).
If ESRD is present, assign N18.6.
Example
“Type 2 diabetes with CKD stage 3” → E11.22 + N18.3
Related Reading: Nationwide Nephrology Billing Services
3
E11.29 – Type 2 Diabetes Mellitus With Other Kidney Complications
E11.29 is used when:
Kidney involvement is documented
The condition is related to diabetes
But it does not fall under nephropathy or CKD staging
Examples may include:
Diabetic renal disorder, unspecified
Early kidney changes related to diabetes
Renal complications not clearly defined as CKD or nephropathy
If the documentation is vague, coders should ensure clarification from the provider.
E11.3 Series – Diabetes with Ophthalmic Complications
1
E11.31 – Type 2 Diabetes Mellitus With Unspecified Diabetic Retinopathy
Use E11.31 when the provider documents diabetic retinopathy but does not specify:
Type
Laterality (right, left, bilateral)
Whether macular edema is present
Examples of documentation that map to E11.31:
“Diabetic retinopathy”
“Retinopathy due to diabetes”
“Changes consistent with diabetic eye disease”
If the provider mentions macular edema or specifies the severity (mild, moderate, severe), a more specific code from the E11.32–E11.39 range is required.
2
E11.319 – Type 2 Diabetes Mellitus With Unspecified Retinopathy, Without Macular Edema
Assign E11.319 when documentation states:
Diabetic retinopathy (type unspecified)
Without mention of macular edema
No severity or laterality indicated
This is one of the most common codes used in ophthalmology reports when retinopathy is noted but details are minimal.
Examples:
“NPDR without macular edema” (if severity is unspecified)
“Retinopathy related to diabetes, no edema seen”
3
Other Retinopathy Codes in the E11.3 Series
The E11.3 range includes more specific classifications depending on severity and presence of macular edema. These are used when documentation includes:
Mild nonproliferative diabetic retinopathy
Moderate NPDR
Severe NPDR
Proliferative diabetic retinopathy
Presence or absence of macular edema
Laterality (right, left, bilateral)
Coders should assign the most specific code supported by the record. If any key details are missing, providers may need clarification
E11.4 Series – Diabetes with Neurological Complications
1
E11.40 – Type 2 Diabetes Mellitus With Diabetic Neuropathy, Unspecified
Use E11.40 when documentation indicates neuropathy caused by diabetes, but does not clarify the type. This includes common phrases such as:
“Diabetic neuropathy”
“Neuropathy secondary to diabetes”
“Nerve damage due to diabetes”
If the provider does not specify whether it is mononeuropathy, polyneuropathy, or autonomic neuropathy, E11.40 is the correct choice
2
E11.41 – Type 2 Diabetes Mellitus With Diabetic Mononeuropathy
Assign E11.41 when the record documents mononeuropathy associated with diabetes. Examples include:
Single nerve involvement
Diabetic cranial nerve palsy
Diabetic median or ulnar nerve mononeuropathy
This code reflects localized nerve involvement rather than systemic.
3
E11.42 – Type 2 Diabetes Mellitus With Diabetic Polyneuropathy
E11.42 is one of the most commonly used neuropathy codes, and your Queries.csv confirms high search interest in it. Use this code when documentation includes:
“Diabetic polyneuropathy”
“Peripheral neuropathy due to diabetes”
“Length-dependent neuropathy in diabetes”
“Bilateral foot neuropathy due to diabetes”
Because polyneuropathy is the most frequent neurological manifestation in diabetes, this code appears often in outpatient and podiatry notes. Providers treating diabetic neuropathy can benefit from our podiatry billing services, which focus on accurate coding for nerve-related complications and lower-extremity care
4
E11.43 – Type 2 Diabetes Mellitus With Diabetic Autonomic Neuropathy
Use E11.43 when autonomic involvement is clearly documented. Examples include:
Orthostatic hypotension due to diabetes
Gastroparesis of diabetic origin
Diabetic bladder dysfunction
Autonomic neuropathy symptoms linked to diabetes
Autonomic manifestations are less common but still important to code accurately
E11.5 Series – Diabetes with Circulatory Complications
1
E11.51 – Type 2 Diabetes Mellitus With Diabetic Peripheral Angiopathy
Use E11.51 when the provider documents:
Peripheral angiopathy due to diabetes
PAD/PVD associated with diabetes
Vascular insufficiency caused by diabetes
Lower-extremity arterial narrowing linked to diabetes
Common documentation examples include:
“Diabetic peripheral arterial disease”
“Ischemic changes in feet due to diabetes”
“Peripheral angiopathy in diabetic patient”
If the provider also documents rest pain, ulcers, or gangrene, additional codes are required
2
E11.52 – Type 2 Diabetes Mellitus With Gangrene
Assign E11.52 when gangrene is documented as a complication of diabetes. Gangrene reflects advanced vascular compromise and usually requires immediate attention. Documentation that supports E11.52 includes:
“Gangrene of foot due to diabetes”
“Ischemic gangrene in diabetic patient”
“Dry or wet gangrene related to diabetes”
Additional Coding Guidance
If a specific site of gangrene is noted, assign a site-specific code (e.g., I96).
Ulcers associated with gangrene require L97.x in addition to E11.52.
If PAD is documented along with gangrene, both conditions should be coded.
3
E11.59 – Type 2 Diabetes Mellitus With Other Circulatory Complications
Use E11.59 when circulatory involvement is documented but does not clearly fall under peripheral angiopathy or gangrene. Examples:
Early vascular changes in diabetes
Impaired circulation not otherwise specified
Microangiopathy due to diabetes
This is a good “catch-all” category for vascular issues that are linked to diabetes but lack specific classification.
Coding Tips for Circulatory Complications
If PAD or gangrene is due to another condition (e.g., smoking-related PAD), the relationship must be documented before assigning E11.51 or E11.52.
Use Combination Coding When Required
Common combinations from real GSC queries:
E11.51 + I73.9 — Diabetes with PAD
E11.52 + I96 — Diabetes with gangrene
E11.51 + L97.x — Diabetes with foot ulcer and PAD
Watch for Laterality
If the ulcer or ischemia is on a specific foot or leg, always include the correct laterality code in the L97.x series
E11.8 – Type 2 Diabetes Mellitus With Unspecified Complications
Use E11.8 when the provider documents that the patient has a complication of diabetes, but the specific type of complication is not clearly described. Examples of documentation that may require E11.8:
“Diabetes with complications” (no details provided)
“Diabetic complications – unspecified”
“Diabetes with systemic involvement”
Important Notes
E11.8 should never be used when a specific complication is documented elsewhere in the note.
If the complication is identifiable (e.g., neuropathy, CKD, ulceration), use the appropriate specific code instead.
When the documentation is unclear, consider requesting clarification from the provider.
This code is useful, but should be used conservatively to avoid over-generalization
E11.9 – Type 2 Diabetes Mellitus Without Complications (Extended Clarification)
E11.9 is used when:
No complications are documented
Provider notes “controlled,” “stable,” or “well-managed” diabetes
The visit is for routine follow-up or medication review
There is no evidence of end-organ involvement
Additional ICD-10 Codes That May Be Required
Even in uncomplicated diabetes, the following may apply:
Z79.4 – Long-term insulin use
Z79.84 – Long-term use of oral hypoglycemic agents
Z71.3 – Dietary management counseling (if applicable)
When to Use E11.8 vs. E11.9
| Code | When to Use | Documentation Example |
|---|---|---|
| E11.8 | A complication exists, but it is unspecified | “Diabetes with complications,” no further detail |
| E11.9 | No complications are documented | “Type 2 diabetes, well controlled” |
Correctly distinguishing between these two codes ensures accurate coding and aligns with provider intent.
ICD-10 Combination Coding for Type 2 Diabetes
ICD-10-CM requires coders to report both the diabetes code and the related secondary code when the complication involves:
Chronic kidney disease
Ulcers
Gangrene
Peripheral artery disease
Vision loss
Medication use
Pressure vs non-pressure ulcers
These combinations provide the clinical detail needed to reflect severity, site, and progression of the disease.
1
Diabetes With Chronic Kidney Disease (E11.22 + N18.x)
Use this combination when the provider documents CKD caused by or associated with diabetes.
Primary Code:
- E11.22 – Type 2 diabetes with CKD
Add a Secondary Code for CKD Stage:
- N18.1–N18.5 for stages 1–5
- N18.6 for end-stage renal disease
- N18.9 for CKD, unspecified
Example Documentation → Coding
- “Type 2 diabetes with CKD stage 3”
→ E11.22 + N18.3 - “Diabetes with ESRD on dialysis”
→ E11.22 + N18.6
→ Add dialysis codes if documented
2
Diabetes With Foot Ulcer (E11.621 + L97.x)
When a foot ulcer is due to diabetes:
Primary Code:
E11.621 – Diabetes with foot ulcer
Secondary Code (Required):
Use an L97.x code to indicate:
Site (ankle, heel, midfoot, toes)
Laterality (left, right)
Depth (skin breakdown, fat layer exposed, necrosis, bone involvement)
Example
“Ulcer of left heel due to diabetes, necrosis of bone”
→ E11.621 + L97.423
Coding diabetic foot ulcers requires precise combination coding—our wound care billing service provide accurate code selection along with modifier usage where necessary to get you paid for wound care and ulcer complications.
3
Diabetes With Gangrene (E11.52 + I96)
Use this combination when gangrene is documented as a diabetes-related complication.
Primary Code:
E11.52 – Diabetes with gangrene
Additional Secondary Code:
I96 – Gangrene, not elsewhere classified
Example
“Gangrene of right forefoot due to diabetes”
→ E11.52 + I96
→ Add ulcer codes if present
→ Add PAD codes if documented (I73.x)
4
Diabetes With Peripheral Artery Disease (E11.51 + I73.x)
When PAD or PVD is documented as related to diabetes:
Primary Code:
E11.51 – Diabetes with peripheral angiopathy
Secondary Code:
I73.9 – Peripheral vascular disease, unspecified
(or a more specific I73.x code if documented)
Example
“Type 2 diabetes with PAD”
→ E11.51 + I73.9
5
Diabetes With Vision Loss (E11.3x + H54.x)
When diabetic retinopathy leads to visual impairment:
Primary Code
Appropriate E11.3x retinopathy code
Secondary Code
H54.x – Level of visual impairment
Example
“Severe NPDR in left eye with vision loss”
→ E11.339 + H54.62
6
Long-Term Insulin Use (Z79.4) & Oral Medication Use (Z79.84)
These secondary codes do not replace the E11 code—they are added when medications are part of ongoing diabetes management.
Use Z79.4 when:
The patient is on long-term insulin therapy
The provider notes “insulin dependent” or “long-term insulin use”
Use Z79.84 when:
The patient uses long-term oral hypoglycemics
The patient is on metformin, sulfonylureas, SGLT2 inhibitors, etc.
Examples
“Type 2 diabetes on long-term insulin”
→ E11.x + Z79.4“Type 2 diabetes managed with metformin only”
→ E11.x + Z79.84
7
Diabetes With Pressure Ulcers (E11.x + L89.x)
If the ulcer is a pressure ulcer, not a diabetic neuropathic ulcer:
Use the appropriate E11.x code based on diabetes status
Add the L89.x code to specify staging and location
This distinction matters because many coders incorrectly use L97.x for pressure ulcers.
Z79.4 and Z79.84 – Long-term Medication Use with Diabetes
This section clarifies when to add the appropriate Z-codes and how they interact with E11-series codes.
1
Z79.4 – Long-Term (Current) Use of Insulin
Use Z79.4 when the provider documents that the patient is on long-term or chronic insulin therapy. Typical documentation supporting Z79.4 includes:
“Patient on long-term insulin”
“Insulin dependent” (for Type 2 patients only)
“Insulin therapy for ongoing management”
“Basal insulin + mealtime insulin regimen”
Important Clarifications
Z79.4 does not replace the E11 code.
It is added to show the medication component of the treatment plan.
If the patient is using insulin temporarily (e.g., for short-term inpatient management), do not assign Z79.4.
Examples
“Type 2 diabetes on long-term insulin therapy”
→ E11.x + Z79.4
2
Z79.84 – Long-Term Use of Oral Antidiabetic Medications
Use Z79.84 when documentation shows that the patient is taking ongoing oral diabetes medications, such as:
Metformin
Sulfonylureas
DPP-4 inhibitors
SGLT2 inhibitors
Thiazolidinediones
GLP-1 receptor agonists (if oral formulation)
When to Use Z79.84
Z79.84 applies when:
The patient uses oral medication as part of long-term management
Medication refills, adjustments, or follow-ups are documented
The provider indicates continued pharmacologic therapy
Example
“T2DM managed with metformin”
→ E11.x + Z79.84
3
Using Both Codes Together: Z79.4 + Z79.84
When a patient uses both insulin and oral medications, assign both codes:
Z79.4 – Long-term insulin
Z79.84 – Long-term oral medications
Example
“Type 2 diabetes treated with metformin and long-term insulin”
→ E11.x + Z79.4 + Z79.84
Do Not Use Z79.4 for Type 1 Diabetes
Although type 1 patients rely on insulin, Z79.4 is not assigned with Type 1 diabetes. Their insulin use is considered inherent to the condition and does not require a separate Z-code.
Pediatric Coding for type 2 Diabetes (E11 Series)
Coding Type 2 Diabetes in Children Using the E11 Series
In ICD-10-CM, children with Type 2 diabetes are still coded using the same E11.x series codes as adults. There is no separate pediatric category—the code depends solely on the complication documented, not the patient’s age.
When a child has no complications
Assign E11.9 when Type 2 diabetes is documented without any associated conditions:
“Child with Type 2 diabetes, stable”
“Adolescent with new-onset T2DM, no complications”
When complications exist
If complications such as nephropathy, hyperglycemia, retinopathy, or neuropathy are present, select the appropriate subcode from the E11 series. Examples:
E11.65 – With hyperglycemia
E11.21 – With diabetic nephropathy
E11.40 – With neuropathy
E11.31 – With retinopathy
The coding rules remain exactly the same as for adults.
Medication Use Codes in Children
If a child with Type 2 diabetes is taking insulin or oral medications long-term, assign the appropriate Z-codes:
Z79.4 – Long-term insulin use
Z79.84 – Long-term oral antidiabetic medications
These codes apply regardless of the patient’s age, as long as long-term therapy is documented.
When NOT to Use the E11 Series
A child with prediabetes or abnormal glucose findings should not be coded with E11.x. Instead:
R73.03 – Prediabetes
R73.9 – Hyperglycemia, unspecified (if diabetes is not diagnosed)
This avoids overcoding and maintains accuracy for early-stage glucose abnormalities in children.
Diagnostic Clarity Is Essential
Children may have:
Obesity
Insulin resistance
Atypical presentations
Overlapping features of T1DM or MODY
If the clinician does not explicitly diagnose Type 2 diabetes, the coder should not assume the type. Follow ICD-10-CM guidelines:
If diabetes type is unspecified, default to Type 2 unless the provider indicates otherwise
Conclusion
Accurate coding for Type 2 diabetes relies on understanding how ICD-10-CM organizes the E11 category and how complications should be linked based on clinical documentation. The ICD-10-CM Official Guidelines for Coding and Reporting clearly state that when the provider does not specify the type of diabetes, the default is Type 2 diabetes mellitus. They also instruct coders to “code the highest level of specificity” and use combination codes when diabetes directly causes a secondary condition.
The Centers for Medicare & Medicaid Services (CMS) further emphasize the importance of complete complication coding for accurate risk adjustment and reimbursement. Conditions such as CKD, neuropathy, retinopathy, and chronic ulcers significantly impact a patient’s clinical profile and must be captured using the appropriate E11.x subcodes along with the corresponding secondary codes (e.g., N18.x for CKD or L97.x for ulcers). CMS’ Hierarchical Condition Category (HCC) guidelines highlight that diabetes with chronic complications carries different risk weights than uncomplicated diabetes, reinforcing the need for proper specificity. Avail our billing support for chronic care and complex conditions.
Clinical standards also align with these coding rules. The American Diabetes Association (ADA) acknowledges that diabetes-related kidney disease, neuropathy, retinopathy, and vascular disease are among the most common long-term complications of Type 2 diabetes, and ICD-10-CM reflects this by dedicating entire subcategories to these conditions. ADA guidance confirms that documentation should clearly state when complications are attributable to diabetes, which directly supports the structure of ICD-10’s combination codes.
By following these official guidelines and using the appropriate E11.x codes, coders ensure:
More accurate claim submission
Fewer denials and audits
Proper reflection of clinical severity
Compliance with CMS and ADA standards
Accurate population-based reporting and risk adjustment
With consistent application of ICD-10-CM rules and a clear understanding of how complications are classified, coders can confidently assign the correct diagnosis codes and support both clinical integrity and compliant billing.
Learn how the best medical billing company in USA provides effective medical coding solutions! Contact us Now
Frequently Asked Questions
What is the ICD-10 code for Type 2 diabetes mellitus?
Type 2 diabetes is coded under the E11 category in ICD-10-CM. The exact code depends on whether complications such as neuropathy, CKD, retinopathy, ulcers, or hyperglycemia are documented.
When should E11.9 be used?
Use E11.9 when Type 2 diabetes is documented without any complications and the provider does not indicate uncontrolled blood sugar, organ involvement, or associated conditions.
How do I code Type 2 diabetes with chronic kidney disease?
Assign E11.22 for diabetes with CKD, and add the appropriate N18.x code to report the CKD stage. Example: E11.22 + N18.3 for CKD stage 3.
What code should be used for diabetic neuropathy?
Diabetic neuropathy is coded using the E11.4x series. Use E11.40 when the type of neuropathy is unspecified. Use E11.42 for polyneuropathy. Use E11.41 for mononeuropathy.
How do I code a diabetic foot ulcer?
Use E11.621 for Type 2 diabetes with foot ulcer, and assign a secondary L97.x code to describe the ulcer’s site, depth, severity, and laterality.
What is the ICD-10 code for Type 2 diabetes with hyperglycemia?
Use E11.65 when the provider documents hyperglycemia, poorly controlled diabetes, or elevated blood glucose readings related to Type 2 diabetes.
Should I code long-term insulin use separately?
Yes. For patients with Type 2 diabetes who are on long-term insulin therapy, add Z79.4 along with the E11.x code. For long-term oral antidiabetic medications, use Z79.84
What if the provider doesn’t specify the type of diabetes?
ICD-10-CM guidelines instruct coders to default to Type 2 diabetes unless the provider clearly documents otherwise.
Can multiple diabetes complication codes be used together?
Yes. If a patient has multiple complications—such as CKD, neuropathy, or foot ulcers—each complication should be coded using the appropriate E11.x subcodes and required secondary codes.
How is pediatric Type 2 diabetes coded?
Children with Type 2 diabetes are coded using the same E11.x series as adults. The code depends on the documented complication, not the patient’s age.
