Atrial fibrillation ICD-10 code
The ICD-10-CM code for atrial fibrillation is I48.91 — unspecified atrial fibrillation. 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 afib, a fib, af.
The mistake coders make here
I48.91 (unspecified) is the lazy default. The chart almost always distinguishes paroxysmal (I48.0), persistent (I48.1-), or permanent (I48.2-), and the specific code holds up far better under review.
Putting atrial fibrillation on a claim? Check the claim’s diagnosis codes free — Excludes1 conflicts, header codes and missing seventh characters, before it goes out.
All ICD-10-CM codes for atrial fibrillation
9 of 14 are billable. Green means you can submit it as-is.
| Code | Use it when |
|---|---|
| I48.91 | Unspecified atrial fibrillation |
| I48.0 | Paroxysmal atrial fibrillation |
| I48.11 | Longstanding persistent atrial fibrillation |
| I48.19 | Other persistent atrial fibrillation |
| I48.20 | Chronic atrial fibrillation, unspecified |
| I48.21 | Permanent atrial fibrillation |
| I48 | Atrial fibrillation and flutternot billable on its own |
| I48.2 | Chronic atrial fibrillationnot billable on its own |
| I48.1 | Persistent atrial fibrillationnot billable on its own |
| I48.9 | Unspecified atrial fibrillation and atrial flutternot billable on its own |
| I48.92 | Unspecified atrial flutter |
| I48.3 | Typical atrial flutter |
| I48.4 | Atypical atrial flutter |
| I49.0 | Ventricular fibrillation and flutternot billable on its own |
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