| spp | Crestron SIMPL+ Parameters Data |
| spr | Visual FoxPro Form Program |
| sprite | BYOB Sprite |
| sprite | Scratch v1 Sprite |
| sprite2 | Scratch v2 Sprite |
| sprite3 | Scratch v3 Sprite Data |
| sprx | Signed PPU Relocatable Executable |
| spt | ESPL Programming File |
| spy | WinTECH Socket Spy Log |
| spz | Crestron SIMPL Compiled Program |
| sq | Sysquake SQ Application |
| sqc | SQR Common Code |
| sqlce | Microsoft SQL Server SQLCE Data |
| sqljet | Eclipse JET SQL Template |
| sqml | Standard Query Markup Language Document |
| sqn | SAS for Mac 6 DMDB Database |
| sqo | Squeak Object |
| sqr | SQR Script |
| sqt | Compiled SQR Script |
| squ | NI LabWindows/CVI Test Executive Toolkit Sequence Data |
| src | General Source Code File |
| src | ProWorx NXT Search Data |
| src | Win32Forth Sequential Block Data |
| srd | Sybase PowerBuilder DataWindow |
| sre | Windows CE Embedded Rom Image |
| srm | Sybase PowerBuilder Menu |
| srq | Sybase PowerBuilder Query Object |
| srs | Sybase PowerBuilder Structure |
| sru | Sybase PowerBuilder User Object |
| srw | Sybase PowerBuilder Window |