| gizSouth Giziga | giz | Afroasiatic | | | 5 · Developing |
| lmfSouth Lembatabahasa Lembata Selatan | lmf | — | | | 6a · Vigorous |
| ajpSouth Levantine Arabic | ajp | Afroasiatic | | 11.6 m | 3 · Wider Communication |
| mqmSouth Marquesanèo ènata | mqm | Austronesian | | | 7 · Shifting |
| ktsSouth Muyu | kts | Trans–New Guinea | | | 6a · Vigorous |
| spxSouth Picene | spx | Indo-European | | | |
| xslSouth SlaveyDene Zhatıé | xsl | Na-Dene | | | 7 · Shifting |
| srvSouth Sorsoganon | srv | Austronesian | | | 6a · Vigorous |
| omwSouth Tairora | omw | Trans–New Guinea | | | 5 · Developing |
| mcySouth Watut | mcy | Austronesian | | | 6b · Threatened |
| tvkSoutheast Ambrym | tvk | Austronesian | | | 5 · Developing |
| vbbSoutheast Babar | vbb | Austronesian | | | 6a · Vigorous |
| dksSoutheastern Dinka | dks | Nilo-Saharan | | | 4 · Educational |
| pomSoutheastern Pomo | pom | Pomoan | | | 8b · Nearly Extinct |
| tcuSoutheastern Tarahumara | tcu | Uto-Aztecan | | | 7 · Shifting |
| agySouthern Alta | agy | Austronesian | | | 6b · Threatened |
| altSouthern Altaiалтайдыҥ тил | alt | Turkic | | 55,720 | 2 · Provincial |
| amsSouthern Amami Ōshima | ams | Japonic | | 1,800 | 7 · Shifting |
| aycSouthern Aymara | ayc | Aymaran | | | 6a · Vigorous |
| bfsSouthern Bai | bfs | — | | | 6a · Vigorous |
| bccSouthern Balochi | bcc | — | | | 5 · Developing |
| bzcSouthern Betsimisaraka Malagasy | bzc | Austronesian | | | 6a · Vigorous |
| bivSouthern Birifor | biv | Niger–Congo | | | 5 · Developing |
| cafSouthern Carrier | caf | Na-Dene | | | 8a · Moribund |
| blnSouthern Catanduanes Bikol | bln | Austronesian | | | 6a · Vigorous |
| crjSouthern East Cree | crj | — | | | 8a · Moribund |
| gheSouthern Ghale | ghe | Bodish | | | 6a · Vigorous |
| grjSouthern Grebo | grj | Niger–Congo | | | 6a · Vigorous |
| hmySouthern Guiyang Hmong | hmy | Hmong–Mien | | | 6a · Vigorous |
| haxSouthern Haida | hax | — | | | 8b · Nearly Extinct |
| kscSouthern Kalinga | ksc | Austronesian | | | 4 · Educational |
| kssSouthern Kissi | kss | Niger–Congo | | | 5 · Developing |
| kjdSouthern Kiwai | kjd | Kiwaian | | | 5 · Developing |
| sdhSouthern Kurdish | sdh | Indo-European | | 3 m | 6a · Vigorous |
| lrrSouthern Lorung | lrr | Sino-Tibetan | | | 6b · Threatened |
| luzSouthern Luriلری دۊمنی | luz | — | | 1 m | 6a · Vigorous |
| snmSouthern Ma'di | snm | Nilo-Saharan | | | 6a · Vigorous |
| hmaSouthern Mashan Hmong | hma | Hmong–Mien | | | 6b · Threatened |
| nanSouthern Min閩南語 | nan | Sino-Tibetan | +5 | 48.3 m | 6a · Vigorous |
| mnnSouthern Mnong | mnn | — | | | 6a · Vigorous |
| mvfSouthern Mongolian | mvf | Mongolic | | | 6b · Threatened |
| nblSouthern NdebeleIsiNdebele | nbl | Niger–Congo | | 640,000 | 1 · National |
| nbwSouthern Ngbandi | nbw | Niger–Congo | | 105,000 | 6a · Vigorous |
| nikSouthern Nicobarese | nik | Austroasiatic | | | 6b · Threatened |
| nsdSouthern Nisu | nsd | Sino-Tibetan | | | 8a · Moribund |
| nxlSouthern Nuaulu | nxl | Austronesian | | | 6b · Threatened |
| osuSouthern One | osu | Torricelli | | | 6b · Threatened |
| pbtSouthern Pashto | pbt | Indo-European | +1 | 10.9 m | 1 · National |
| cspSouthern Pinghua | csp | Sino-Tibetan | | | |
| peqSouthern Pomo | peq | Pomoan | | | 8b · Nearly Extinct |
| slhSouthern Puget Sound Salish | slh | Salishan | | | 9 · Dormant |
| hmsSouthern Qiandong Miao | hms | Hmong–Mien | | | 6a · Vigorous |
| qxsSouthern Qiang | qxs | Sino-Tibetan | | | 6b · Threatened |
| rgsSouthern Roglai | rgs | Austronesian | | | 6a · Vigorous |
| ssbSouthern Sama | ssb | Austronesian | | | 5 · Developing |
| smaSouthern Samiåarjelsaemien gïele | sma | Uralic | | 600 | 2 · Provincial |
| skdSouthern Sierra Miwok | skd | Yok-Utian | | | 10 · Extinct |
| laaSouthern Subanen | laa | Austronesian | | | 5 · Developing |
| souSouthern Thai | sou | Kra–Dai | | 4.5 m | 5 · Developing |
| itdSouthern Tidung | itd | Austronesian | | | 6a · Vigorous |
| tixSouthern Tiwa | tix | Tanoan | | | 6b · Threatened |
| tjsSouthern Tujia | tjs | Sino-Tibetan | | | 8a · Moribund |
| tceSouthern Tutchone | tce | Na-Dene | | | 8a · Moribund |
| uzsSouthern Uzbekاوزبیک تورکچه | uzs | Western Karluk | | 4.2 m | 2 · Provincial |
| yuxSouthern Yukaghir | yux | Uralic | | 50 | 8a · Moribund |
| diqSouthern Zaza | diq | Indo-European | | | 5 · Developing |
| plvSouthwest Palawano | plv | Austronesian | | | 6a · Vigorous |
| nwiSouthwest Tanna | nwi | Austronesian | | | 5 · Developing |
| dikSouthwestern Dinka | dik | Nilo-Saharan | | | 4 · Educational |
| hmgSouthwestern Guiyang Hmong | hmg | Hmong–Mien | | | 6a · Vigorous |
| hmhSouthwestern Huishui Hmong | hmh | Hmong–Mien | | | 6a · Vigorous |
| nsvSouthwestern Nisu | nsv | Sino-Tibetan | | | 6b · Threatened |
| tlaSouthwestern Tepehuan | tla | Uto-Aztecan | | | 6a · Vigorous |
| swwSowa | sww | Austronesian | | | 10 · Extinct |
| sowSowanda | sow | Border | | | 6a · Vigorous |
| vmqSoyaltepec Mixtec | vmq | Central American Indian languages | | | 6b · Threatened |
| spaSpanishespañol | spa | Indo-European | +24 | 555.6 m | 1 · National |
| sspSpanish Sign Languagelengua de signos española | ssp | — | | | 6b · Threatened |
| sptSpiti Bhoti | spt | — | | | 6a · Vigorous |
| spoSpokane | spo | — | | | 9 · Dormant |
| squSquamishSḵwx̱wú7mesh sníchim | squ | Salishan | | 1 | 8b · Nearly Extinct |
| srnSranan TongoSranantongo | srn | Dutch-based creole languages | | 126,000 | 3 · Wider Communication |
| sciSri Lankan Creole Malay | sci | — | | 46,000 | 6b · Threatened |
| sqsSri Lankan Sign Language | sqs | — | | 12,800 | 6a · Vigorous |
| arbStandard Arabicالعربية الفصحى | arb | Afroasiatic | | 335 m | 1 · National |
| cmnStandard Chinese現代標準漢語 | cmn | Sino-Tibetan | +4 | 897.1 m | |
| ekkStandard Estonian | ekk | Uralic | | 1.2 m | 1 · National |
| zsmStandard Malaybahasa Melayu Standard | zsm | Austronesian | | | |
| zghStandard Moroccan Amazighⵜⴰⵎⴰⵣⵉⵖⵜ ⵜⴰⵏⴰⵡⴰⵢⵜ | zgh | — | | 2.7 m | 1 · National |
| tgkStandard Tajikзабони адабӣ | tgk | — | | | |
| stlStellingwarfs | stl | Indo-European | | | 5 · Developing |
| sbuStod Bhoti | sbu | — | | | 6b · Threatened |
| jihStodse | jih | Sino-Tibetan | | 4,100 | 6b · Threatened |
| stoStoney | sto | Hoka-Sioux | | | 7 · Shifting |
| sqqSu' | sqq | Austroasiatic | | | 6b · Threatened |
| mswSua | msw | Niger–Congo | | | 6a · Vigorous |
| szpSuabobahasa Inanwatan | szp | — | | | 6b · Threatened |
| seoSuarmin | seo | — | | | 7 · Shifting |
| suhSuba | suh | Niger–Congo | | | 5 · Developing |
| sscSuba-Simbiti | ssc | Niger–Congo | | | 6a · Vigorous |
| sutSubtiaba | sut | Central American Indian languages | | | 9 · Dormant |
| apdSudanese Arabic | apd | — | | 31.9 m | 3 · Wider Communication |
| xsvSudovian | xsv | Indo-European | | | |
| sueSuena | sue | Trans–New Guinea | | | 5 · Developing |
| sugSuganga | sug | Trans–New Guinea | | | 6b · Threatened |
| kzsSugut Dusun | kzs | Austronesian | | | 6b · Threatened |
| swiSui | swi | — | | 300,000 | 6a · Vigorous |
| suiSuki | sui | Trans–New Guinea | | 3,500 | 5 · Developing |
| ctdSukte | ctd | Sino-Tibetan | | | 5 · Developing |
| subSuku | sub | Niger–Congo | | | 6a · Vigorous |
| sukSukumaJìsùgǔmà | suk | Niger–Congo | | 5.4 m | 5 · Developing |
| sykSukur | syk | — | | | 6a · Vigorous |
| zsuSukurum | zsu | Austronesian | | 1,160 | 6a · Vigorous |
| sznSula | szn | Austronesian | | 20,000 | 6a · Vigorous |
| suaSulka | sua | — | | | 4 · Educational |
| srgSulod | srg | Austronesian | | | 6b · Threatened |
| sivSumariup | siv | Sepik | | | 7 · Shifting |
| sixSumau | six | Trans–New Guinea | | | 6a · Vigorous |
| smwSumbawaBasa Samawa | smw | Austronesian | | 300,000 | 6a · Vigorous |
| suwSumbwa | suw | Niger–Congo | | | 6a · Vigorous |
| tcmSumeri | tcm | — | | | 6b · Threatened |
| suxSumerian𒅴𒂠 | sux | — | | | |
| nsmSumi | nsm | Sino-Tibetan | | | 4 · Educational |
| sumSumo | sum | Misumalpan | | | Severely endangered |
| sskSunam | ssk | Sino-Tibetan | | | 6b · Threatened |
| sunSundaneseBasa Sunda | sun | Austronesian | | 32.4 m | 5 · Developing |
| sjgSungor | sjg | — | | | 6a · Vigorous |
| mrbSungwadia | mrb | Austronesian | | | 6a · Vigorous |
| suzSunwar̐ | suz | Sino-Tibetan | | | 6b · Threatened |
| syoSuoy | syo | Austroasiatic | | | 8a · Moribund |
| sppSupyire | spp | Niger–Congo | | | 5 · Developing |
| tdlSur | tdl | Niger–Congo | | | 6a · Vigorous |
| sgjSurgujia | sgj | Indo-European | | | 6a · Vigorous |
| suqSuri | suq | Nilo-Saharan | | | 4 · Educational |
| sgdSurigaonon | sgd | Austronesian | | | 4 · Educational |
| sjpSurjapuri | sjp | — | | | 6a · Vigorous |
| sgzSursurunga | sgz | Austronesian | | | 5 · Developing |
| sdeSurubu | sde | Niger–Congo | | | 6a · Vigorous |
| sruSuruí | sru | Tupian | | 2,000 | 6a · Vigorous |
| susSusuSosoxui | sus | Niger–Congo | | 2.4 m | 4 · Educational |
| ssuSusuami | ssu | Trans–New Guinea | | | 8b · Nearly Extinct |
| sdjSuundi | sdj | Niger–Congo | | | 6a · Vigorous |
| szvSuwu | szv | Niger–Congo | | | 6b · Threatened |
| suySuyá | suy | Macro-Jê | | 350 | 6a · Vigorous |
| svaSvan | sva | Kartvelian | | 15,000 | 7 · Shifting |
| swgSwabianSchwäbisch | swg | Indo-European | | 820,000 | 5 · Developing |
| swaSwahiliKiswahili | swa | Niger–Congo | +10 | 15.4 m | |
| cswSwampy Cree | csw | — | | | 6b · Threatened |
| sswSwazisiSwati | ssw | Niger–Congo | | 2 m | 1 · National |
| sweSwedishsvenska | swe | East Scandinavian | | 12.4 m | 1 · National |
| swlSwedish Sign Language | swl | — | | 8,000 | 4 · Educational |
| sggSwiss-German Sign LanguageDeutschschweizer Gebärdensprache | sgg | — | | | 5 · Developing |
| slfSwiss-Italian Sign Language | slf | — | | 300 | 5 · Developing |
| soxSwo | sox | Niger–Congo | | | 6b · Threatened |
| shzSyenara | shz | Niger–Congo | | | 6a · Vigorous |
| kzaSyer-Tenyer | kza | Niger–Congo | | | 6a · Vigorous |
| sylSylhetiꠘꠣꠉꠞꠤ ꠜꠣꠡꠣ | syl | Indo-European | +13 | 14 m | 3 · Wider Communication |
| sycSyriacܠܫܢܐ ܣܘܪܝܝܐ | syc | Afroasiatic | | 575,000 | 9 · Second language only |