N21.0 Calculus in bladder

Billable ICD-10-CM code, FY2026.

Applicable to

• Calculus in diverticulum of bladder
• Urinary bladder stone

Excludes2 (not included here)

• staghorn calculus (N20.0)

Applies from N21 Calculus of lower urinary tract

Includes

• calculus of lower urinary tract with cystitis and urethritis

MS-DRG index

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

Approximate ICD-9-CM (GEMs)

• 594.0 Calculus in diverticulum of bladder (approximate)
• 594.1 Other calculus in bladder (approximate)

Code annotations containing back-references to N21.0

Back-references to N21.0

• Type 2 Excludes: N32 Other disorders of bladder ("calculus of bladder (N21.0)")

Diagnosis Index entries for N21.0

• Calculus, calculi, calculous › bladder (encysted) (impacted) (urinary) (diverticulum)
• Calculus, calculi, calculous › cystic
• Calculus, calculi, calculous › diverticulum › bladder
• Calculus, calculi, calculous › vesical (impacted)
• Cystitis (exudative) (hemorrhagic) (septic) (suppurative) › calculous
• Cystolithiasis
• Stone (s) › bladder (diverticulum)
• Stone (s) › urinary (duct) (impacted) (passage) › bladder (diverticulum)

Nearby codes

• N21 Calculus of lower urinary tract
• N21.0 Calculus in bladder (this code)
• N21.1 Calculus in urethra
• N21.8 Other lower urinary tract calculus
• N21.9 Calculus of lower urinary tract, unspecified