| Name | Other Name | Family | Nativ Name | ISO6391 Code | ISO6392T Code | ISO6392B Code | ISO6393 Code | Notes |
|---|---|---|---|---|---|---|---|---|
| Cornish | Indo-European | Kernewek | kw | cor | cor | cor | ||
| Kirghiz | Kyrgyz | Turkic | Кыргызча; Кыргыз тили | ky | kir | kir | kir | |
| Latin | Indo-European | latine; lingua latina | la | lat | lat | lat | ancient | |
| Luxembourgish | Letzeburgesch | Indo-European | Lëtzebuergesch | lb | ltz | ltz | ltz | |
| Ganda | Niger–Congo | Luganda | lg | lug | lug | lug | ||
| Limburgan | Limburger;Limburgish | Indo-European | Limburgs | li | lim | lim | lim | |
| Lingala | Niger–Congo | Lingála | ln | lin | lin | lin | ||
| Lao | Tai–Kadai | ພາສາລາວ | lo | lao | lao | lao | ||
| Lithuanian | Indo-European | lietuvių kalba | lt | lit | lit | lit | ||
| Luba-Katanga | Niger–Congo | Kiluba | lu | lub | lub | lub | also known as Luba-Shaba |