Non-Billable / Non-Specific Code
ICD-10-CM N21 is the diagnosis code for Calculus of lower urinary tract. This code falls under the section "Urolithiasis" within Chapter 14 — Diseases of the genitourinary system (N00-N99). It is a non-billable/non-specific ICD-10-CM code that should not be used for reimbursement. A more specific sub-code is required for billing. Medical coders and healthcare providers use this code to document and classify diagnoses in electronic health records, insurance claims, and clinical databases.
Always refer to the official ICD-10-CM Tabular List for complete coding guidelines. Ensure documentation supports the specificity of the code selected. When in doubt, consult a certified medical coder or the latest CMS guidelines.
Understanding where N21 sits in the ICD-10-CM classification helps ensure proper coding:
No, N21 is a non-billable/non-specific code. You should use a more specific sub-code for billing and reimbursement.
N21 is the ICD-10-CM diagnosis code for "Calculus of lower urinary tract". It is used by healthcare providers to classify and document this condition in medical records and insurance claims.
N21 is located in Section N20-N23 — "Urolithiasis" within Chapter 14 of the ICD-10-CM Tabular List.
N21 has 4 sub-code(s) that provide more specific detail: N21.0, N21.1, N21.8, N21.9.
Use N21 when the patients documented diagnosis matches "Calculus of lower urinary tract" and the clinical documentation supports this level of specificity. Always verify with the latest ICD-10-CM guidelines and payer requirements.
The ICD-10-CM code for Calculus of lower urinary tract is N21.
No, N21 is non-billable. Use a more specific sub-code for primary diagnosis billing.
N21 is in Chapter 14 of the ICD-10-CM Tabular List.
Yes, N21 is a valid ICD-10-CM code for the 2026 fiscal year, subject to official CMS updates.