ICD-10-CM Tabular Index · Chapter 14 · FY 2026 N21

Calculus of lower urinary tract (N21) ICD-10-CM

The N21 code range covers calculus of lower urinary tract with 5 ICD-10-CM diagnosis codes. 4 of them are billable and valid for claim submission in fiscal year 2026, and the category headers group them but cannot themselves be billed.

✓ Built from the official CMS FY 2026 datasetEffective Oct 1, 2025 – Sep 30, 2026
5
Diagnosis Codes
4
Billable Codes
N21
Code Range
N20–N23
Parent Section

Includes

This note appears immediately under a three character code title to further define, or give examples of, the content of the category.

ICD-10-CM

Codes in the N21 Range 5 codes · 4 billable

5 of 5 shown
  • N21 Calculus of lower urinary tractNon-billable
  • N21.0 Calculus in bladder
  • N21.1 Calculus in urethra
  • N21.8 Other lower urinary tract calculus
  • N21.9 Calculus of lower urinary tract, unspecified

About the N21 Code Range

The ICD-10 code N21 and its subcodes classify types of stones, or calculi, specifically located in the lower urinary tract. These codes are used when documenting conditions such as bladder stones or urethral stones.

This section includes N21.0 for a calculus in the bladder, covering common terms like urinary bladder stone or uric acid urolithiasis. The N21.1 code identifies stones found in the urethra. Other less specific lower urinary tract stones fall under N21.8, including terms like vesicoureteric junction calculus. When the location of the stone within the lower urinary tract is not specified, N21.9 is used. For anyone searching the ICD-10 code for bladder stones or urethral calculi, these codes provide precise classification and help ensure correct medical coding and billing for these conditions.

Questions About This Page

How many billable codes are in the N21 range?

Of the 5 codes in this range, 4 are billable and valid for claim submission from October 1, 2025 through September 30, 2026. Category header codes group them but cannot be reported on claims.

What does the N21 range classify?

The range classifies calculus of lower urinary tract. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.

Related References

Source: CMS FY 2026 ICD-10-CM Tabular List and order file, effective October 1, 2025 through September 30, 2026.