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.
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
The type is the code, and 'chronic' has its own answer
I48.0 is paroxysmal (self-terminating, usually within seven days). Persistent splits into I48.11, longstanding persistent (continuous for more than a year), and I48.19, other persistent. Chronic splits into I48.20, chronic atrial fibrillation unspecified, and I48.21, permanent (the provider and patient have accepted it and stopped trying to restore rhythm). I48.91 is atrial fibrillation with no type documented. 'Chronic AF' with nothing else indexes to I48.20; 'persistent AF' with no duration to I48.19. Flutter is separate: I48.3 typical, I48.4 atypical, I48.92 unspecified. AF documented alongside flutter is two codes.
Anticoagulation, ablation status and the post-operative case
Z79.01 is long-term use of anticoagulants and belongs on the claim for the patient on warfarin or a DOAC; Z79.02 covers antiplatelets. Prior ablation with the AF still present is still an I48 code; a history of AF that has resolved is Z86.79. Post-operative atrial fibrillation is coded as the AF type documented; there is no dedicated post-operative AF code, and I97.89 (other post-procedural complication of the circulatory system) is added only when the provider explicitly documents it as a complication of the surgery rather than an expected occurrence.
Rapid ventricular response, and what AF is not
'AF with RVR' is coded to the type of AF alone; RVR describes the rate and has no code of its own, and R00.0 (tachycardia unspecified) is not added because the fast rate is integral to the arrhythmia. Sick sinus syndrome is I49.5, supraventricular tachycardia I47.1-, and atrial premature beats I49.1: none are AF. A patient whose stroke is attributed to AF gets the stroke code (I63.-) first when the admission is for the stroke, with the I48 code second.
Common questions
- What is the ICD-10 code for atrial fibrillation, unspecified?
- I48.91. Use it only when the type is not documented; paroxysmal is I48.0, persistent I48.19 (longstanding persistent I48.11), chronic unspecified I48.20 and permanent I48.21.
- What is the ICD-10 code for chronic atrial fibrillation?
- I48.20, chronic atrial fibrillation, unspecified, when the note says chronic and nothing more. If the provider documents permanent atrial fibrillation, I48.21.
- How do I code atrial fibrillation with rapid ventricular response?
- Code the type of atrial fibrillation only. RVR has no code and the tachycardia is integral to the arrhythmia, so R00.0 is not reported.