| rt4 | SAS/GIS TIGER Index to Alternate Feature Names |
| rt5 | SAS/GIS TIGER Feature Name List |
| rt6 | SAS/GIS TIGER Additional Address and ZIP Code |
| rta | Adobe RoboHelp RTA Data File |
| rtc | BrainVoyager QX Regions-of-interest TC Data |
| rtc | CARE-S InfoWorks Real Time Control Data |
| rtd | Retina Network Security Scanner Output |
| rtda | Microsoft Enterprise Voice Route Helper Data |
| rtgs | Oracle FLEXCUBE RTGS Message |
| rth | ANSYS Results File |
| rti2 | Indexed Rainbow Tables Data |
| rtk | Adobe RoboHelp RTK Data File |
| rtm | Navicat Report File |
| rtmp | RTMP Stream Data |
| rtn | Carlson Survey Road Network File |
| rtp | GROMACS Residue Topology |
| rtr | Astrotite 200X Offline Data Repair File |
| rtree | General R-Tree Data |
| rts | Royal TS v1 Document |
| rts | Adobe RoboHelp RTS Data File |
| rtstn | Audials Station Data |
| rtsx | Royal TS v2 Document |
| rttex | Proton Texture Data |
| rtwsh | Audials Radiotracker Wishlist |
| ru | Java Russian Font Properties Data |
| rui | SPEFO Rectified Spectrum Data |
| ruj | Oracle Database Recovery-Unit Journal |
| ruk | Recorder 6 Rucksack Data |
| run | Runscanner Scan Result |
| rut | Novapoint Grid File |
