K51 — Ulcerative colitis
Is K51 billable?
No — K51 is a non-billable header code. K51 groups more specific codes and cannot be submitted on a claim. A valid ICD-10-CM code must be reported at the highest level of specificity available in its branch. Select one of the 49 billable codes beneath K51.
Billable codes under this header
- K51.00Ulcerative (chronic) pancolitis without complications
- K51.20Ulcerative (chronic) proctitis without complications
- K51.30Ulcerative (chronic) rectosigmoiditis without complications
- K51.40Inflammatory polyps of colon without complications
- K51.50Left sided colitis without complications
- K51.80Other ulcerative colitis without complications
- K51.90Ulcerative colitis, unspecified, without complications
- K51.011Ulcerative (chronic) pancolitis with rectal bleeding
- K51.012Ulcerative (chronic) pancolitis with intestinal obstruction
- K51.013Ulcerative (chronic) pancolitis with fistula
- K51.014Ulcerative (chronic) pancolitis with abscess
- K51.018Ulcerative (chronic) pancolitis with other complication
- K51.019Ulcerative (chronic) pancolitis with unspecified complications
- K51.211Ulcerative (chronic) proctitis with rectal bleeding
- K51.212Ulcerative (chronic) proctitis with intestinal obstruction
- K51.213Ulcerative (chronic) proctitis with fistula
- K51.214Ulcerative (chronic) proctitis with abscess
- K51.218Ulcerative (chronic) proctitis with other complication
- K51.219Ulcerative (chronic) proctitis with unspecified complications
- K51.311Ulcerative (chronic) rectosigmoiditis with rectal bleeding
- K51.312Ulcerative (chronic) rectosigmoiditis with intestinal obstruction
- K51.313Ulcerative (chronic) rectosigmoiditis with fistula
- K51.314Ulcerative (chronic) rectosigmoiditis with abscess
- K51.318Ulcerative (chronic) rectosigmoiditis with other complication
- K51.319Ulcerative (chronic) rectosigmoiditis with unspecified complications
- K51.411Inflammatory polyps of colon with rectal bleeding
- K51.412Inflammatory polyps of colon with intestinal obstruction
- K51.413Inflammatory polyps of colon with fistula
- K51.414Inflammatory polyps of colon with abscess
- K51.418Inflammatory polyps of colon with other complication
- K51.419Inflammatory polyps of colon with unspecified complications
- K51.511Left sided colitis with rectal bleeding
- K51.512Left sided colitis with intestinal obstruction
- K51.513Left sided colitis with fistula
- K51.514Left sided colitis with abscess
- K51.518Left sided colitis with other complication
- K51.519Left sided colitis with unspecified complications
- K51.811Other ulcerative colitis with rectal bleeding
- K51.812Other ulcerative colitis with intestinal obstruction
- K51.813Other ulcerative colitis with fistula
- K51.814Other ulcerative colitis with abscess
- K51.818Other ulcerative colitis with other complication
- K51.819Other ulcerative colitis with unspecified complications
- K51.911Ulcerative colitis, unspecified with rectal bleeding
- K51.912Ulcerative colitis, unspecified with intestinal obstruction
- K51.913Ulcerative colitis, unspecified with fistula
- K51.914Ulcerative colitis, unspecified with abscess
- K51.918Ulcerative colitis, unspecified with other complication
- K51.919Ulcerative colitis, unspecified with unspecified complications
K51 at a glance
| Code | K51 |
|---|---|
| Description | Ulcerative colitis |
| Billable | No — header code |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
Excludes1 — never code together
The conditions below can never be reported together with K51 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
- Crohn's disease [regional enteritis] (K50.-)
Use additional code
Report an additional code alongside K51 to fully describe the condition. K51 is sequenced first.
Excludes1 — never code together — inherited from K50-K52
The conditions below can never be reported together with K51 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
Excludes2 — not included here — inherited from Chapter 11
The conditions below are not part of K51, but a patient may have both at the same time. When documentation supports it, K51 and the excluded code may both be reported.
- certain conditions originating in the perinatal period (P04-P96)
- certain infectious and parasitic diseases (A00-B99)
- complications of pregnancy, childbirth and the puerperium (O00-O9A)
- congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)
- endocrine, nutritional and metabolic diseases (E00-E88)
- injury, poisoning and certain other consequences of external causes (S00-T88)
- neoplasms (C00-D49)
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
What codes fall under K51? (7)
- K51.0Ulcerative (chronic) pancolitisnot billable
- K51.2Ulcerative (chronic) proctitisnot billable
- K51.3Ulcerative (chronic) rectosigmoiditisnot billable
- K51.4Inflammatory polyps of colonnot billable
- K51.5Left sided colitisnot billable
- K51.8Other ulcerative colitisnot billable
- K51.9Ulcerative colitis, unspecifiednot billable
How long has K51 existed?
K51 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.
Which codes are confused with K51?
ICD-10-CM declares these codes mutually exclusive with K51 — exactly one of each pair can be correct for a given encounter.