| Salishan languages | Salish-Sprache | sal | |
| Samaritan Aramaic | Samaritanisch | sam | |
| Sami languages (Other) | Samisch | smi | |
| Samoan | Samoanisch | smo | sm |
| Sandawe | Sandawe-Sprache | sad | |
| Sango | Sango-Sprache | sag | sg |
| Sanskrit | Sanskrit | san | sa |
| Santali | Santali | sat | |
| Sardinian | Sardisch | srd | sc |
| Sasak | Sasak | sas | |
| Saxon, Low; German, Low; Low Saxon; Low German | Niedersächsisch; Niederdeutsch | nds | |
| Scots | Schottisch | sco | |
| Scottish Gaelic; Gaelic | Gälisch-Schottisch | gla | gd |
| Selkup | Selkupisch | sel | |
| Semitic (Other) | Andere semitische Sprachen | sem | |
| Sepedi; Northern Sotho; Pedi | Sotho-Sprache (Nord) | nso | |
| Serbian | Serbisch | srp/scc | sr |
| Serer | Serer-Sprache | srr | |
| Shan | Schan-Sprache | shn | |
| Shona | Schona-Sprache | sna | sn |
| Sichuan Yi; Nuosu | Nosu | iii | ii |
| Sicilian | Sizilianisch | scn | |
| Sidamo | Sidamo-Sprache | sid | |
| Sign languages | Zeichensprachen | sgn | |
| Siksika | Blackfoot-Sprache | bla | |
| Sindhi | Sindhi-Sprache | snd | sd |
| Sinhala; Sinhalese | Singhalesisch | sin | si |
| Sino-Tibetan (Other) | Andere sinotibetische Sprachen | sit | |
| Siouan languages | Sioux-Sprachen | sio | |
| Skolt Sami | Skoltsaamisch | sms | |
| Slave (Athapascan) | Slave-Sprache | den | |
| Slavic (Other) | Andere slawische Sprachen | sla | |
| Slovak | Slowakisch | slo/slk | sk |
| Slovenian | Slowenisch | slv | sl |
| Sogdian | Sogdisch | sog | |
| Somali | Somali | som | so |
| Songhai languages | Songhai-Sprache | son | |
| Soninke | Soninke-Sprache | snk | |
| Sorbian languages | Sorbisch | wen | |
| Sotho, Northern; Pedi; Sepedi | Sotho-Sprache (Nord) | nso | |
| Sotho, Southern | Süd-Sotho-Sprache | sot | st |
| South American Indian (Other) | Andere Indianersprachen (Südamerika) | sai | |
| Southern Altai | Altaisch | alt | |
| Southern Sami | Südsaamisch | sma | |
| South Ndebele | Ndebele-Sprache (Transvaal) | nbl | nr |
| Spanish; Castilian | Spanisch | spa | es |
| Sranan Tongo | Srananisch | srn | |
| Sukuma | Sukuma-Sprache | suk | |
| Sumerian | Sumerisch | sux | |
| Sundanese | Sundanesisch | sun | su |
| Susu | Susu | sus | |
| Swahili | Swahili | swa | sw |
| Swati | Swasi-Sprache | ssw | ss |
| Swedish | Schwedisch | swe | sv |
| Swiss German; Alemannic; Alsatian | Hochalemannisch | gsw | |
| Syriac | Syrisch | syr | |
| Tagalog | Tagalog | tgl | tl |
| Tahitian | Tahitisch | tah | ty |
| Tai (Other) | Andere Thaisprachen | tai | |
| Tajik | Tadschikisch | tgk | tg |
| Tamashek | Tamaseq | tmh | |
| Tamil | Tamil | tam | ta |
| Tatar | Tatarisch | tat | tt |
| Telugu | Telugu-Sprache | tel | te |
| Tereno | Tereno-Sprache | ter | |
| Tetum | Tetum-Sprache | tet | |
| Thai | Thailändisch | tha | th |
| Tibetan | Tibetisch | tib/bod | bo |
| Tigre | Tigre-Sprache | tig | |
| Tigrinya | Tigrinja-Sprache | tir | ti |
| Timne | Temne-Sprache | tem | |
| Tiv | Tiv-Sprache | tiv | |
| tlhIngan-Hol; Klingon | Klingonisch | tlh | |
| Tlingit | Tlingit-Sprache | tli | |
| Tok Pisin | Neumelanesisch | tpi | |
| Tokelau | Tokelauanisch | tkl | |
| Tonga (Nyasa) | Tonga (Bantusprache, Sambia) | tog | |
| Tonga (Tonga Islands) | Tongaisch | ton | to |
| Tsimshian | Tsimshian-Sprache | tsi | |
| Tsonga | Tsonga-Sprache | tso | ts |
| Tswana | Tswana-Sprache | tsn | tn |
| Tumbuka | Tumbuka-Sprache | tum | |
| Tupi languages | Tupi | tup | |
| Turkish | Türkisch | tur | tr |
| Turkish, Ottoman (1500-1928) | Osmanisch (1500-1928) | ota | |
| Turkmen | Turkmenisch | tuk | tk |
| Tuvalu | Elliceanisch | tvl | |
| Tuvinian | Tuwinisch | tyv | |
| Twi | Twi-Sprache | twi | tw |
