N20.1 Calculus of ureter

Billable ICD-10-CM code, FY2026. Acts as a Complication or Comorbidity (CC) as a secondary diagnosis.

Applicable to

• Calculus of the ureteropelvic junction
• Ureteric stone

Applies from N20 Calculus of kidney and ureter

Applicable to

• Calculous pyelonephritis

Excludes1 (never code together)

• nephrocalcinosis (E83.59)
• that with hydronephrosis (N13.2)

MS-DRG index

Defines the logic of DRG(s) 693-694 in MDC 11.

Approximate ICD-9-CM (GEMs)

• 592.1 Calculus of ureter (approximate)

Code annotations containing back-references to N20.1

Back-references to N20

• Type 2 Excludes: N13 Obstructive and reflux uropathy ("calculus of kidney and ureter without hydronephrosis (N20.-)")

Diagnosis Index entries for N20.1

• Calculus, calculi, calculous › ureter (impacted) (recurrent)
• Calculus, calculi, calculous › ureteropelvic junction
• Ureteritis › due to calculus

Nearby codes

• N20 Calculus of kidney and ureter
• N20.0 Calculus of kidney
• N20.1 Calculus of ureter (this code)
• N20.2 Calculus of kidney with calculus of ureter
• N20.9 Urinary calculus, unspecified