FSSO
| Acronym | Definition |
|---|---|
| FSSO | Fame Single Sign on |
| FSSO | Free State Symphony Orchestra (South Africa) |
| FSSO | Federated Single Sign-On |
| FSSO | Flag Ship Service Organization (Scientology) |
| FSSO | Fire Support Station Operator |
| FSSO | Foreign Service Staff Officer |
| FSSO | Flight Standards Satellite Office |