2026 ICD-10-CM Diagnosis Code N23Unspecified renal colic

ICD-10-CM Codes›N00–N99›N20-N23›N23

ICD-10-CM N23
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

N23 is a billable ICD-10-CM diagnosis code for unspecified renal colic. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 693 through 694. Coders also document this condition as finding of sensation of kidney. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified and unspecified diseases of kidney and ureters.

Code Identity

ICD-10-CM Code
N23
Billable Status
Yes — Valid for Submission
Code Describes
Unspecified renal colic
Short Description
Unspecified renal colic
Same as the full description in the CMS dataset.
Chapter
N20-N23
Urolithiasis

Code Classification

ChapterN00–N99Diseases of the genitourinary system
SectionN20-N23Urolithiasis
CategoryN23Unspecified renal colic
This CodeN23Unspecified renal colic

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Finding of sensation of kidney
  • Renal angle pain
  • Renal colic
  • Renal pain
  • Tenderness of kidney
  • Ureteric colic
  • Ureteric pain
  • Urinary tract tenderness

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Colic(bilious) (infantile) (intestinal) (recurrent) (spasmodic)
      • kidney
    • Colic(bilious) (infantile) (intestinal) (recurrent) (spasmodic)
      • nephritic
    • Colic(bilious) (infantile) (intestinal) (recurrent) (spasmodic)
      • renal
    • Colic(bilious) (infantile) (intestinal) (recurrent) (spasmodic)
      • ureter
    • Nephralgia
    • Pain(s)
      • kidney
    • Pain(s)
      • ureter
    • Pain(s)
      • urinary (organ) (system)
    • Ureteralgia

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR GEN006
Other specified and unspecified diseases of kidney and ureters
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Renal Colic

    a severe intermittent and spasmodic pain in the lower back radiating to the groin, scrotum, and labia which is most commonly caused by a kidney stone (renal calculus) passing through the ureter or by other urinary track blockage. it is often associated with nausea, vomiting, fever, restlessness, dull pain, frequent urination, and hematuria.

Patient EducationClinical

Kidney Stones

A kidney stone is a solid piece of material that forms in the kidney from substances in the urine. It may be as small as a grain of sand or as large as a pearl. Most kidney stones pass out of the body without help from a doctor. But sometimes a stone will not go away.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert N23 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
788.0 Renal colic
Exact Match The mapping is direct, with no qualifiers.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About N23Overview

Is N23 (Unspecified renal colic) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report unspecified renal colic on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does N23 group to?

When unspecified renal colic is the principal diagnosis on an inpatient stay, it groups to MS-DRG 693, 694, with relative weights from 0.7817 to 1.3445 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of N23?

Under the General Equivalence Mappings, unspecified renal colic converts to ICD-9-CM 788.0 (renal colic). The mapping is a direct match.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.