| E/OS | — | — | GNU General Public License, version 2.0 |
| EasyNAS | — | — | — |
| EasyOS | — | — | — |
| EasyPeasy | — | — | GNU General Public License |
| EComStation | XL Software Europe | — | proprietary license |
| ECos | — | — | eCos-2.0 |
| Edos | The Computer Software Company | — | — |
| Edubuntu | Canonical Ltd. | — | GNU General Public License |
| EducaAndOS | — | — | — |
| Educanix | — | — | GNU General Public License |
| Eduknoppix | — | — | GNU General Public License |
| EdulibreOs | — | — | — |
| EduLinux | — | — | — |
| Edutice | — | — | — |
| Elastix | — | — | GNU General Public License, proprietary license |
| Elbrus Linux | Moscow Center of SPARC Technologies | — | — |
| Elbuntu | — | 2006 | GNU General Public License |
| Element OS | — | — | — |
| Elementary OS | — | — | GNU Lesser General Public License, GNU General Public License |
| ELinOS | SYSGO | — | GNU General Public License |
| Elive | — | — | GNU General Public License |
| Embeddable Linux Kernel Subset | — | — | GNU General Public License |
| Embox | — | — | 2-clause BSD License |
| Emdebian Grip | — | — | GNU General Public License |
| Emmabuntüs | — | — | — |
| Emteria.OS | — | — | — |
| EmuELEC | — | — | — |
| EMUI | Huawei | — | proprietary license |
| EmuTOS | — | — | GNU General Public License, version 2.0 |
| EndeavourOS | — | 2019 | — |
| Endian Firewall | — | — | GNU General Public License |
| Endless OS | Endless Computer | — | — |
| EnGarde Secure Linux | — | — | — |
| Enlisy | — | — | — |
| Enso OS | — | — | GNU General Public License |
| EOS | ETA Systems | — | — |
| EPOC | Psion | 1989 | — |
| ERIKA Enterprise | — | — | GPL linking exception |
| Erythros | — | — | Unlicense |
| Escape | — | — | GNU General Public License, version 2.0 |
| Escuelas Linux | — | — | — |
| Essence | Nakst | — | MIT License |
| Estobuntu | — | — | — |
| Estrella Roja | — | — | — |
| EterTICs GNU/Linux | — | 2014 | — |
| EU OS | — | — | — |
| EulerOS | Huawei | — | — |
| Eumel | — | — | — |
| Event Driven Executive | IBM | — | — |
| EWS-UX | NEC | — | — |
| EXEC | International Computers Limited | — | — |
| Exherbo | — | — | — |
| EXOS | Enterprise Computers | — | — |
| ExTiX | — | — | — |
| ExtremeXOS | Extreme Networks | — | — |
| Ez-WifiBroadcast | — | — | — |
| EZeY | — | — | GNU General Public License, version 2.0 |