| L4Linux | — | — | GNU General Public License |
| LainOS | — | — | — |
| Lakka | — | — | — |
| LAN Manager | 3Com, Microsoft | — | proprietary license |
| LEAF Project | — | — | GNU General Public License |
| LEDE | — | — | GNU General Public License |
| Leeenux | — | — | — |
| LegoOS | — | — | GNU General Public License, version 2.0 |
| LeJOS | — | — | — |
| Lernstick | — | — | — |
| LeWa OS | — | — | — |
| LG UX | LG Electronics | — | — |
| LibertyBSD | — | — | permissive free software license |
| Libranet | — | — | — |
| LibreCMC | — | — | GNU General Public License, version 2.0 |
| LibreELEC | — | — | GNU General Public License, version 2.0 |
| LightOS | The light phone inc. | — | — |
| Lightweight Portable Security | United States Department of Defense | 2011 | — |
| Lihuen GNU/Linux | — | — | — |
| Lilith | — | — | MIT License |
| LiMux | — | — | — |
| LineageOS | — | 2016 | GNU General Public License, version 2.0, Apache License |
| LineageOS for microG | — | — | — |
| Linkat | Generalitat of Catalonia | — | GNU General Public License |
| Linpus Linux | — | — | GNU General Public License |
| Linux for PlayStation 2 | Sony Interactive Entertainment | — | — |
| Linux Galiza | — | — | — |
| Linux Kamarada | — | — | — |
| Linux Kodachi | — | — | Apache Software License 2.0 |
| Linux Lite | Jerry Bezencon | — | — |
| Linux Mint | — | 2006 | GNU General Public License |
| Linux Mint Debian Edition | — | — | GNU General Public License |
| Linux Router Project | — | 1997 | GNU General Public License |
| Linux Unified Kernel | — | — | GNU General Public License, version 2.0 |
| Linux XP | — | — | GNU General Public License |
| LinuX-gamers | — | — | — |
| Linux-Musterlösung | — | — | GNU General Public License |
| Linux4Space | — | — | — |
| Linuxacessivel.org | — | — | GNU General Public License |
| LinuxBBQ | — | — | — |
| Linuxcare Bootable Toolbox | Linuxcare | — | — |
| LinuxConsole | — | — | — |
| LinuxEDU | — | — | European Union Public Licence |
| LinuxFX | — | — | — |
| LinuxMCE | — | — | — |
| Linuxmuster.net | — | — | GNU General Public License |
| LinuxPPC | — | — | GNU General Public License |
| LinuxTLE | National Electronics and Computer Technology Center | — | — |
| LinVDR | — | — | — |
| Linvo | — | — | — |
| Lisa OS | Apple Inc. | — | — |
| LiteOS | — | — | GNU General Public License, 3-clause BSD License |
| Livermore Time Sharing System | Lawrence Livermore National Laboratory | — | — |
| LliureX | Generalitat Valenciana | — | GNU General Public License |
| LNX-BBC | — | — | — |
| Loc-OS | — | — | GNU General Public License, version 2.0 |
| LOCUS | University of California, Los Angeles | — | proprietary license |
| LogoDIDACT | — | — | — |
| Loong Arch Linux | — | — | — |
| Loongnix | Loongson Technology Co., Ltd. | — | — |
| LOUD | — | — | — |
| Luberri Linux | — | — | — |
| Lubuntu | Canonical Ltd. | — | GNU General Public License |
| Lunar Linux | — | — | GNU General Public License |
| LuneOS | — | — | Apache License |
| LUnix | — | — | GNU General Public License, version 2.0 |
| LuxOS | — | — | GNU General Public License v3.0 or later |
| LXLE Linux | — | — | — |
| Lycoris | — | — | — |
| LynxOS | Lynx Software Technologies | — | — |
| Ładowacz | — | — | — |