K35.80
Billable

Unspecified acute appendicitis

Billable / Specific Code

What is Unspecified acute appendicitis?

ICD-10-CM K35.80 is the diagnosis code for Unspecified acute appendicitis. This code falls under the section "Diseases of appendix" within Chapter 11 — Diseases of the digestive system (K00-K95). It is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes. Medical coders and healthcare providers use this code to document and classify diagnoses in electronic health records, insurance claims, and clinical databases.

💡 Inclusions

Coding Guidelines for K35.80

✅ This Code Includes

  • Acute appendicitis NOS
  • Acute appendicitis without (localized) (generalized) peritonitis

ICD-10-CM Code Hierarchy

Understanding where K35.80 sits in the ICD-10-CM classification helps ensure proper coding:

Related Codes

Frequently Asked Questions

Is K35.80 a billable ICD-10-CM code?

Yes, K35.80 is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes.

What does K35.80 mean?

K35.80 is the ICD-10-CM diagnosis code for "Unspecified acute appendicitis". It is used by healthcare providers to classify and document this condition in medical records and insurance claims.

What is the parent code of K35.80?

The parent code of K35.80 is K35.8 ("Other and unspecified acute appendicitis"). K35.80 provides a more specific classification within this category.

What section is K35.80 in?

K35.80 is located in Section K35-K38 — "Diseases of appendix" within Chapter 11 of the ICD-10-CM Tabular List.

When should I use K35.80?

Use K35.80 when the patients documented diagnosis matches "Unspecified acute appendicitis" and the clinical documentation supports this level of specificity. Always verify with the latest ICD-10-CM guidelines and payer requirements.

People Also Ask

What is the ICD-10 code for Unspecified acute appendicitis?

The ICD-10-CM code for Unspecified acute appendicitis is K35.80.

Can K35.80 be used for primary diagnosis?

Yes, K35.80 can be used as a primary diagnosis code since it is billable and specific.

What chapter is K35.80 in?

K35.80 is in Chapter 11 of the ICD-10-CM Tabular List.

Is K35.80 valid for 2026?

Yes, K35.80 is a valid ICD-10-CM code for the 2026 fiscal year, subject to official CMS updates.

See Also

← PreviousK35.8Other and unspecified acute appendicitisNext →K35.89Other acute appendicitis
Code Details
K35.80
Unspecified acute appendicitis
Billable / Specific Code
11 — Diseases of the digestive system (K00-K95)
K35-K38 — Diseases of appendix
2026 ICD-10-CM