ICD-10 Code J98.11 – Atelectasis (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code J98.11 – Atelectasis
What it is
Atelectasis means part of the lung has partially or fully collapsed, so less air reaches that area. It is a descriptive diagnosis, not a cause, and you should code it when the record identifies this finding.
Clinical signs
Clinical features vary; refer to documentation. Common findings may include reduced breath sounds, diminished chest expansion, or imaging showing lung volume loss or collapse.
When to use this code
Use J98.11 when the provider documents atelectasis as a current diagnosis, radiology impression, or discharge condition. It may appear after surgery, with mucus plugging, or during shallow breathing, but you should code only what is clearly documented.
If the note specifies a different underlying disorder causing the collapse, code both conditions when supported. Check documentation for laterality, acuity, and whether the atelectasis is postoperative or incidental.
Do not use for
Do not use this code for pneumonia, pleural effusion, or general shortness of breath unless atelectasis is specifically documented. Do not assume collapsed lung means pneumothorax.
Coding tip
Confirm whether the atelectasis is a finding, complication, or postoperative condition, and code the documented cause when available.