| tar | Tape Archive |
| taraa | Tape Archive Split Archive |
| tardist | IRIX TAR Distribution Archive |
| targz | Unix Gzipped TAR Archive |
| taz | Unix Gzipped TAR Archive |
| tbk | The Bat! Backup Archive |
| tbz | Bzip Compressed Tape Archive |
| tbz2 | Bzip2 Compressed Tape Archive |
| tce | Tiny Core Linux Extension |
| tck | BMISuite BMIScan Compressed Archive |
| tgz | Unix Gzipped TAR Archive |
| thr | THOR Compressed Data |
| tibkp | Titanium Backup Data |
| tibx | Acronis Backup v12 Archive |
| to4 | Top 4 Compressed Data |
| toppkg | TopSolid Package |
| tpafz | YouMinds Composer Portable Archive |
| tpkg | tpkg-builder data |
| tpxz | Pixz Compressed Tarball |
| tsep | Tekla Structures Extension Package |
| ttpkg | TomTom Package |
| txz | XZ Compressed Tar Archive |
| tz | Compressed Tape Archive |
| tzb | TAR.Z.btoa Compressed Archive |
| tzip | Tzip Compressed Text |
| tzp | TrueZIP Ecnrypted JAR Archive |
| tzr | ANSYS IcePak Project Package |
| uar | Uniface Deployment Archive |
| uas | PhotoImpact Backup Archive |
| uc2 | UltraCompressor 2 Compressed Archive |
| ucas | Unreal Engine 4 Archive |
| uea | Protector Suite QL Encrypted Archive |
| ueed | Uconomix Encryption Engine Encrypted Directory |
| uexp | UE Viewer Package |
| ufa | UFA Compressed Archive |