| Abbreviation | Definition |
|---|---|
| SPI | Security Personnel Inc |
| SPI | Silverstein Properties, Inc. |
| SPI | Simulations Publications Inc |
| SPI | Simulations Publications, Inc. |
| SPI | Singapore Paranormal Investigators |
| SPI | Solar Power Inc |
| SPI | Special Projects International |
| SPI | Staal Private Investigation |
| SPI | Structure Probe, Inc. |
| SPIC | Southern Petrochemical Industries Corporation |
| SPIC | Southern Petrochemicals Industries Corporation |
| SPIL | SciClone Pharmaceuticals International Ltd |
| SPIL | Siliconware Precision Industries Co Ltd |
| SPIL | Student Programmes Ireland Ltd |
| SPIS | South Pacific Information Services |
| SPK | System Programming Korporation |
| SPL | Signal Perfection Ltd |
| SPL | Signal Perfection, LTD. |
| SPLI | SouthEast Personnel Leasing Inc |
| SPM | Sijil Pelajaran Malaysia |