Chronic kidney disease (CKD) ICD-10 code
The ICD-10-CM code for chronic kidney disease (CKD) is N18.9 (chronic kidney disease, unspecified). It is billable and valid for submission on a claim. There are 14 related codes, and which one you use depends on what the documentation supports.
Also written as ckd, renal failure chronic.
The mistake coders make here
Stage 3 was split: N18.30 unspecified, N18.31 stage 3a, N18.32 stage 3b. Coding N18.3 alone is no longer valid. If the patient is also diabetic, the diabetes gets a combination code (E11.22) AND you still code the N18 stage.
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ICD-10-CM codes for chronic kidney disease (CKD)
10 of 14 are billable. Green means you can submit it as-is.
| Code | Use it when |
|---|---|
| N18.9 | Chronic kidney disease, unspecified |
| N18.1 | Chronic kidney disease, stage 1 |
| N18.2 | Chronic kidney disease, stage 2 (mild) |
| N18.30 | Chronic kidney disease, stage 3 unspecified |
| N18.31 | Chronic kidney disease, stage 3a |
| N18.32 | Chronic kidney disease, stage 3b |
| N18.4 | Chronic kidney disease, stage 4 (severe) |
| N18.5 | Chronic kidney disease, stage 5 |
| N18.6 | End stage renal disease |
| N18 | Chronic kidney disease (CKD)not billable on its own |
| N18.3 | Chronic kidney disease, stage 3 (moderate)not billable on its own |
| I12 | Hypertensive chronic kidney diseasenot billable on its own |
| I13 | Hypertensive heart and chronic kidney diseasenot billable on its own |
| E13.22 | Other specified diabetes mellitus with diabetic chronic kidney disease |
Not sure which one? Let the documentation decide.
Answer a few questions about what the chart actually says and we’ll walk you to the code that follows from it.
Once you have the code
- Check the whole claim: Excludes1 conflicts and missing seventh characters, free
- Denial codes explained: what CO-16, CO-97 and the rest actually mean
- Decision guides: walk a chart note to a code, guideline cited
- Everything here that is free, and the one thing no free tool includes
Stage 3 has been three codes since FY2021
N18.30 is stage 3 unspecified, N18.31 is stage 3a (eGFR 45-59) and N18.32 is stage 3b (eGFR 30-44). The provider assigns the stage; a coder does not derive 3a or 3b from the lab value, and a stage documented in the note controls even when the eGFR seems to disagree. The rest of the ladder: N18.1 stage 1, N18.2 stage 2, N18.4 stage 4, N18.5 stage 5, N18.6 end-stage renal disease, and N18.9 unspecified. If the note documents both stage 5 and ESRD, Guideline I.C.14.a.1 says to assign only N18.6. ESRD on dialysis also carries Z99.2, dependence on renal dialysis.
Hypertension and diabetes change the first-listed code
CKD with hypertension is always a combination code: I12.9 for stages 1 to 4 or unspecified, I12.0 for stage 5 or ESRD, and I13.- when heart failure is present too, with the N18.- stage coded second. The relationship is presumed by Guideline I.C.9.a.2 whether or not the provider links them. CKD with diabetes is E11.22 (or E10.22) followed by the N18.- stage, again a presumed relationship under the 'with' convention. A patient with both hypertension and diabetes and CKD carries all three: the I12/I13 code, the E11.22 code and the N18 stage.
Acute on chronic, 'renal insufficiency', and the transplant patient
Acute kidney injury on top of CKD is coded as both: N17.- for the acute injury and N18.- for the stage, because they are different conditions with different implications. 'Renal insufficiency' with no stage and no 'chronic' indexes to N28.9, not to N18, and 'chronic renal insufficiency' indexes to N18.9; query for the stage before settling for either. A kidney transplant recipient with CKD is coded N18.- plus Z94.0, and Guideline I.C.14.a.2 is explicit that the CKD does not by itself mean the transplant has failed.
Common questions
- What is the ICD-10 code for CKD stage 3?
- N18.30 for stage 3 unspecified, N18.31 for stage 3a and N18.32 for stage 3b. The old N18.3 has been invalid since 1 October 2020.
- What is the ICD-10 code for end-stage renal disease?
- N18.6, end stage renal disease, plus Z99.2 if the patient is on dialysis. If stage 5 and ESRD are both documented, report only N18.6.
- How do I code CKD with hypertension and diabetes?
- Three codes: I12.9 (or I12.0 for stage 5/ESRD, or I13.- if heart failure is present) for the hypertensive CKD, E11.22 for the diabetic CKD, and the N18.- code for the stage. Both relationships are presumed by the guidelines.