S20.321 (Blister (nonthermal) of right front wall of thorax) compared with S20.329 (Blister (nonthermal) of unspecified front wall of thorax), from the official CMS tabular data. S20.321 and S20.329 code the same condition on opposite sides.
Same condition; these differ only in which side is documented.
These codes share a category and title and differ only in the side affected. The documentation decides which applies, and a bilateral code is reported only where the code set provides one.
Source: ICD-10-CM tabular list (laterality variant derived from the code title)
Same condition, opposite side. S20.321 and S20.329 name the same condition on opposite sides of the body.
Same category and title, differing only in which side is affected — the documentation decides which one applies, and a bilateral code is reported only where the code set provides one.
| S20.321Blister (nonthermal) of right front wall of thorax | S20.329Blister (nonthermal) of unspecified front wall of thorax | |
|---|---|---|
| Billing status | Non-billable header | Non-billable header |
| Classification | S00-T88 — Injury, Poisoning and Certain Other Consequences of External Causes (S00-T88) | S00-T88 — Injury, Poisoning and Certain Other Consequences of External Causes (S00-T88) |
| Definition | Blister (nonthermal) of right front wall of thorax is a non-billable ICD-10-CM category code (S20.321). | Blister (nonthermal) of unspecified front wall of thorax is a non-billable ICD-10-CM category code (S20.329). |
| 7th character | The appropriate 7th character is to be added to each code from category S20 | The appropriate 7th character is to be added to each code from category S20 |
| Includes | injuries of breast injuries of chest (wall) injuries of interscapular area | injuries of breast injuries of chest (wall) injuries of interscapular area |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources