| Acartophthalmidae Czerny, 1928 | Acartophthalmid flies | 7 | Species | Taxom |
| Acroceridae Leach, 1815 | Hunch-back flies | 152 | Species | Taxom |
| Agromyzidae Fallen, 1823 | Leaf miner flies | 2884 | Species | Taxom |
| Alinkidae Krzemi& 324;ski, 1992 | | 1 | Species | Taxom |
| Anisopodidae Knab, 1912 | Window Midges | 130 | Species | Taxom |
| Ansorgiidae Krzeminski &..., 1993 | | 1 | Species | Taxom |
| Antefungivoridae Rohdendorf, 1938 | | 29 | Species | Taxom |
| Anthomyiidae Robineau-Des..., 1830 | Anthomyiid flies | 1826 | Species | Taxom |
| Anthomyzidae Czerny, 1903 | Anthomyzid flies | 222 | Species | Taxom |
| Apioceridae Bigot, 1852 | Flower-loving flies | 19 | Species | Taxom |
| Apsilocephalidae Nagatomi & al., 1991 | | 4 | Species | Taxom |
| Archisargidae Rohdendorf, 1962 | | 41 | Species | Taxom |
| Archizelmiridae Rohdendorf, 1962 | | 5 | Species | Taxom |
| Asilidae Latreille, 1802 | Assassin flies | 3815 | Species | Taxom |
| Asiochaoboridae Hong & Wang, 1990 | | 4 | Species | Taxom |
| Asteiidae Rondani, 1856 | Asteiid Flies | 55 | Species | Taxom |
| Atelestidae Hennig, 1970 | | 17 | Species | Taxom |
| Athericidae Stuckenberg, 1973 | Athericid flies | 85 | Species | Taxom |
| Aulacigastridae Wollaston, 1864 | Aulacigastrid flies | 22 | Species | Taxom |
| Axymyiidae Rohdendorf, 1946 | Axymyiidae flies | 16 | Species | Taxom |
| Bibionidae Fleming, 1821 | Bibionid flies | 803 | Species | Taxom |
| Blephariceridae Loew, 1861 | Mountain midges | 160 | Species | Taxom |
| Boholdoyidae Kovalev, 1985 | | 3 | Species | Taxom |
| Bolitophilidae Malloch, 1917 | | 8 | Species | Taxom |
| Bombyliidae Latreille, 1802 | Bee Flies | 2170 | Species | Taxom |
| Brachystomatidae Melander, 1908 | | 11 | Species | Taxom |
| Braulidae Egger, 1853 | Bee lice | 7 | Species | Taxom |
| Calliphoridae Brauer & Ber..., 1889 | Blow flies | 1451 | Species | Taxom |
| Camillidae Frey, 1921 | Camillid flies | 22 | Species | Taxom |
| Canaceidae (Jones, 1906) | Beach flies | 53 | Species | Taxom |
| Canacidae Jones, 1906 | Beach Flies | 6 | Species | Taxom |
| Canthyloscelidae Enderlein, 1912 | | 9 | Species | Taxom |
| Carnidae Newman, 1834 | Bird flies | 94 | Species | Taxom |
| Cecidomyiidae Newman, 1834 | Forest Midges | 5259 | Species | Taxom |
| Celyphidae Bigot, 1852 | Beetle flies | 99 | Species | Taxom |
| Ceratopogonidae Newman, 1834 | Biting midge | 3463 | Species | Taxom |
| Chamaemyiidae Hendel, 1910 | Aphid flies | 239 | Species | Taxom |
| Chaoboridae Newman, 1834 | Phantom midge | 118 | Species | Taxom |
| Chimeromyiidae Grimaldi & C..., 2009 | | 8 | Species | Taxom |
| Chironomidae Erichson, 1842 | Chironomids | 7954 | Species | Taxom |
| Chloropidae Schoenherr, 1840 | Chloropid flies | 1776 | Species | Taxom |
| Chyromyidae Hendel, 1916 | Chiromyid flies | 107 | Species | Taxom |
| Clusiidae Schönherr, 1840 | Clusiid flies | 199 | Species | Taxom |
| Coelopidae Hendel, 1910 | Kelp Flies | 14 | Species | Taxom |
| Conopidae Latreille, 1802 | Thick-headed Flies | 418 | Species | Taxom |
| Crosaphididae Kovalev, 1983 | | 1 | Species | Taxom |
| Cryptochetidae Brues & Mela..., 1932 | Cryptochetid Flies | 20 | Species | Taxom |
| Culicidae Meigen, 1818 | Mosquito | 2406 | Species | Taxom |
| Curtonotidae Duda, 1934 | Curtonotid flies | 22 | Species | Taxom |
| Cylindrotomidae (Mulsant, 1842) | Cylindrotomid Crane Flies | 20 | Species | Taxom |
| Cypselosomatidae Hennig, 1958 | Cypselosomatid flies | 13 | Species | Taxom |
| Cypselostomatidae | | 1 | Species | Taxom |
| Deuterophlebiidae Edwards, 1922 | Mountain midges | 9 | Species | Taxom |
| Diadocidiidae Winnertz, 1863 | | 3 | Species | Taxom |
| Diastatidae Hendel, 1917 | Bog flies | 42 | Species | Taxom |
| Dictyodipteridae Rohdendorf, 1961 | | 1 | Species | Taxom |
| Diopsidae Billberg, 1820 | Stalk-eyed flies | 66 | Species | Taxom |
| Ditomyiidae Keilin, 1919 | | 6 | Species | Taxom |
| Dixidae Schiner, 1868 | Dixid Midges | 157 | Species | Taxom |
| Dolichopodidae Latreille, 1809 | Long legged flies | 4009 | Species | Taxom |
| Drosophilidae Rondani, 1856 | Fruit flies | 2071 | Species | Taxom |
| Dryomyzidae Schiner, 1862 | Dryomyzid flies | 51 | Species | Taxom |
| Elliidae Krzeminska, ..., 1993 | | 4 | Species | Taxom |
| Empididae Latreille, 1809 | Balloon flies | 2136 | Species | Taxom |
| Eoditomyiidae Ansorge, 1996 | | 1 | Species | Taxom |
| Eomyiidae Rohdendorf, 1962 | | 1 | Species | Taxom |
| Eopolyneuridae Rohdendorf, 1962 | | 2 | Species | Taxom |
| Eostratiomyiidae Rohdendorf, 1962 | | 1 | Species | Taxom |
| Ephydridae Zetterstedt, 1837 | Brine flies | 1163 | Species | Taxom |
| Eremochaetidae Ussatchov, 1968 | | 23 | Species | Taxom |
| Fanniidae Schnabl & Dz..., 1911 | Latrine flies | 244 | Species | Taxom |
| Fergusoninidae Hennig, 1958 | | 4 | Species | Taxom |
| Fungivoritidae Rohdendorf, 1957 | | 13 | Species | Taxom |
| Glossinidae Theobald, 1903 | Tik-tik flies | 9 | Species | Taxom |
| Gnomuscidae Shcherbakov, 1995 | | 2 | Species | Taxom |
| Gobryidae Mcalpine, 1997 | | 5 | Species | Taxom |
| Grauvogeliidae Krzeminski, 1994 | | 6 | Species | Taxom |
| Helcomyzidae Malloch, 1933 | Helcomyzid flies | 1 | Species | Taxom |
| Heleomyzidae (Westwood, 1840) | Heleomyzid flies | 482 | Species | Taxom |
| Helosciomyzidae Griffiths, 1972 | | 7 | Species | Taxom |
| Hennigmatidae Shcherbakov, 1995 | | 3 | Species | Taxom |
| Hesperinidae Hendel, 1928 | | 10 | Species | Taxom |
| Heterocheilidae Mcalpine, 1991 | Half-bridge flies | 3 | Species | Taxom |
| Heteromyzidae Fallen, 1820 | Heleomyzid flies | 7 | Species | Taxom |
| Hilarimorphidae Hendel, 1936 | Hilarimorphid flies | 11 | Species | Taxom |
| Hippoboscidae Samouelle, 1819 | Keds | 397 | Species | Taxom |
| Hoffeinsmyiidae Michelsen, 2009 | | 1 | Species | Taxom |
| Huaxiasciaritidae (Hong, 2002) | | 28 | Species | Taxom |
| Hybotidae Meigen, 1820 | Dance flies | 1336 | Species | Taxom |
| Hyperpolyneuridae Rohdendorf, 1961 | | 1 | Species | Taxom |
| Ironomyiidae McAlpine & M..., 1966 | Ironic flies | 22 | Species | Taxom |
| Keroplatidae Rondani, 1856 | Fungus gnats | 578 | Species | Taxom |
| Kovalevisargidae Mostovski, 1997 | | 6 | Species | Taxom |
| Lauxaniidae Macquart, 1835 | Beach flies | 1086 | Species | Taxom |
| Limoniidae (Speiser, 1909) | Craneflies | 1007 | Species | Taxom |
| Lonchaeidae Loew, 1861 | Lance Flies | 282 | Species | Taxom |
| Lonchopteridae Curtis, 1839 | Pointed-wing flies | 61 | Species | Taxom |
| Luanpingitidae Zhang, 1986 | | 1 | Species | Taxom |
| Lygistorrhinidae Hendel, 1936 | Long beaked fungus gnat | 18 | Species | Taxom |
| Megamerinidae Hendel, 1913 | Megamerinid flies | 18 | Species | Taxom |
| Mesophantasmatidae Rohdendorf, 1962 | | 1 | Species | Taxom |
| Mesosciophilidae Rohdendorf, 1946 | | 21 | Species | Taxom |
| Micropezidae Illiger, 1798 | Stilt Flies | 184 | Species | Taxom |
| Microphoridae (Chvala, 1983) | | 1 | Species | Taxom |
| Milichiidae Schiner, 1862 | Filth flies | 201 | Species | Taxom |
| Muscidae Latreille, 1802 | Face flies | 3746 | Species | Taxom |
| Musidoromimidae Rohdendorf, 1962 | | 1 | Species | Taxom |
| Mycetobiidae Winnertz, 1863 | | 1 | Species | Taxom |
| Mycetophilidae Newman, 1834 | Fungus Gnat | 6524 | Species | Taxom |
| Mydidae Bezzi, 1903 | Mydas flies | 77 | Species | Taxom |
| Mythicomyiidae Melander, 1902 | Micro Bee Flies | 30 | Species | Taxom |
| Nadipteridae Lukashevich, 1995 | | 4 | Species | Taxom |
| Nannodastiidae Papp, 1980 | | 3 | Species | Taxom |
| Nemestrinidae Macquart, 1834 | Tangle-veined flies | 126 | Species | Taxom |
| Neriidae Hendel, 1916 | Banana stalk flies | 37 | Species | Taxom |
| Neurochaetidae Mcalpine, 1978 | Upside-Down Flies | 6 | Species | Taxom |
| Nothybidae Frey, 1927 | | 9 | Species | Taxom |
| Nycteribiidae Samouelle, 1819 | Bat Flies | 46 | Species | Taxom |
| Nymphomyiidae Tokunaga, 1932 | Nymphomyiid crane flies | 7 | Species | Taxom |
| Odiniidae Hendel, 1920 | Odiniid flies | 33 | Species | Taxom |
| Oestridae Leach, 1815 | Bot flies | 106 | Species | Taxom |
| Opetiidae Rondani, 1856 | Flat-footed flies | 10 | Species | Taxom |
| Opomyzidae (Fallen, 1820) | Opomyzid flies | 96 | Species | Taxom |
| Orientisargidae Zhang, 2012 | | 1 | Species | Taxom |
| Otitidae (Macquart, 1835) | Picture-winged flies | 308 | Species | Taxom |
| Pachyneuridae Schiner, 1864 | Dark-winged fungus gnats | 11 | Species | Taxom |
| Palaeophoridae Rohdendorf, 1951 | | 1 | Species | Taxom |
| Pallopteridae Loew, 1862 | Flutter flies | 70 | Species | Taxom |
| Pantophthalmidae Williston, 1906 | Timber flies | 1 | Species | Taxom |
| Paraxymyiidae Rohdendorf, 1946 | Paxylommatid wasps | 8 | Species | Taxom |
| Pediciidae Osten Sacken, 1860 | Hairy-Eyed Crane Flies | 82 | Species | Taxom |
| Pelecorhynchidae Philip, 1941 | Pelecorhynchid flies | 7 | Species | Taxom |
| Periscelididae Oldenberg, 1914 | Periscelidid Flies | 38 | Species | Taxom |
| Perissommatidae Colless, 1962 | | 7 | Species | Taxom |
| Phaeomyiidae (Verbeke, 1950) | Marsh flies | 7 | Species | Taxom |
| Phoridae Curtis, 1833 | Coffin Flies | 2143 | Species | Taxom |
| Piophilidae Macquart, 1835 | Cheese flies | 105 | Species | Taxom |
| Pipunculidae Walker, 1834 | Big headed flies | 983 | Species | Taxom |
| Platypezidae Fallen, 1815 | Flat footed flies | 162 | Species | Taxom |
| Platystomatidae Schiner, 1862 | Picture-winged flies | 595 | Species | Taxom |
| Pleciodictyidae Rohdendorf, 1962 | | 1 | Species | Taxom |
| Pleciofungivoridae Rohdendorf, 1946 | | 82 | Species | Taxom |
| Pleciomimidae Rodendorf, 1949 | | 30 | Species | Taxom |
| Procramptonomyiidae Kovalev, 1985 | | 6 | Species | Taxom |
| Proneottiophilidae Hennig, 1969 | | 1 | Species | Taxom |
| Protapioceridae Ren, 1998 | | 4 | Species | Taxom |
| Protempididae Ussatchov, 1968 | | 2 | Species | Taxom |
| Protendipedidae Rohdendorf, 1962 | | 3 | Species | Taxom |
| Protobrachyceridae Rohdendorf, 1962 | | 3 | Species | Taxom |
| Protoligoneuridae Rohdendorf, 1962 | | 6 | Species | Taxom |
| Protomphralidae Rohdendorf, 1957 | | 3 | Species | Taxom |
| Protopleciidae Rohdendorf, 1946 | | 50 | Species | Taxom |
| Protorhyphidae Handlirsch, 1906 | | 19 | Species | Taxom |
| Pseudopomyzidae (Mcalpine, 1966) | Banana flies | 6 | Species | Taxom |
| Psilidae Macquart, 1835 | Carrot flies | 335 | Species | Taxom |
| Psychodidae Newman, 1834 | Drain flies | 1858 | Species | Taxom |
| Ptychopteridae Osten Sacken, 1862 | Phantom crane flies | 153 | Species | Taxom |
| Pyrgotidae Schiner, 1868 | Light Flies | 91 | Species | Taxom |
| Rangomaramidae Jaschhof & D..., 2002 | | 8 | Species | Taxom |
| Rhaetaniidae (Krzemiń..., 2002) | | 1 | Species | Taxom |
| Rhagionemestriidae Ussatchov, 1968 | | 9 | Species | Taxom |
| Rhagionempididae Rohdendorf, 1938 | | 5 | Species | Taxom |
| Rhagionidae Latreille, 1802 | Snipe flies | 560 | Species | Taxom |
| Rhiniidae Brauer & Ber..., 1889 | | 15 | Species | Taxom |
| Rhinophoridae Robineau-Des..., 1863 | Woodlouse flies | 126 | Species | Taxom |
| Rhyphidae (Newman, 1834) | | 1 | Species | Taxom |
| Richardidae Snow, 1896 | Richardid flies | 7 | Species | Taxom |
| Richardiidae (Snow, 1896) | Picture-winged flies | 9 | Species | Taxom |
| Ropalomeridae Linder, 1930 | Ropalomerid flies | 2 | Species | Taxom |
| Sarcophagidae Macquart, 1834 | Flesh flies | 1620 | Species | Taxom |
| Scathophagidae Robineau-Des..., 1830 | Dung flies | 690 | Species | Taxom |
| Scatopsidae Newman, 1834 | Dung midges | 290 | Species | Taxom |
| Scenopinidae Burmeister, 1835 | Window Flies | 105 | Species | Taxom |
| Sciaridae Billberg, 1820 | Black fungus gnats | 266 | Species | Taxom |
| Sciomyzidae Fallen, 1820 | Marsh Flies | 411 | Species | Taxom |
| Sepsidae Walker, 1833 | Black scavenger flies | 330 | Species | Taxom |
| Serendipidae Evenhuis, 1994 | | 3 | Species | Taxom |
| Siberhyphidae Kovalev, 1985 | | 1 | Species | Taxom |
| Simuliidae Newman, 1834 | Black flies | 1550 | Species | Taxom |
| Spaniidae (Nagatomi, 1982) | | 3 | Species | Taxom |
| Sphaeroceridae Macquart, 1835 | Dung flies | 1093 | Species | Taxom |
| Strashilidae Rasnitsyn, 1992 | | 3 | Species | Taxom |
| Stratiomyidae Latreille, 1802 | Soldier flies | 1243 | Species | Taxom |
| Streblidae (Kolenati, 1863) | Bat flies | 73 | Species | Taxom |
| Strongylophthalmyiidae Hennig, 1940 | Strongylophthalmyiid flies | 76 | Species | Taxom |
| Syrphidae Latreille, 1802 | Drone flies | 4992 | Species | Taxom |
| Tabanidae Latreille, 1802 | Breeze flies | 2394 | Species | Taxom |
| Tachinidae (Robineau-Des..., 1830) | Bristle Flies | 5078 | Species | Taxom |
| Tachiniscidae (Kertesz, 1903) | | 1 | Species | Taxom |
| Tanyderidae Alexander, 1919 | Primitive crane flies | 44 | Species | Taxom |
| Tanyderophryneidae Rohdendorf, 1962 | | 1 | Species | Taxom |
| Tanypezidae Rondani, 1856 | Stretched-foot flies | 2 | Species | Taxom |
| Tephritidae Newman, 1834 | Fruit flies | 2982 | Species | Taxom |
| Teratomyzidae Hennig, 1969 | Fern Flies | 0 | Species | Taxom |
| Tethepomyiidae Grimaldi & A..., 2008 | | 1 | Species | Taxom |
| Tethinidae (Hendel, 1916) | Tethinid flies | 106 | Species | Taxom |
| Thaumaleidae Bezzi, 1913 | Solitary midges | 117 | Species | Taxom |
| Therevidae Newman, 1834 | Stiletto flies | 469 | Species | Taxom |
| Tipulidae Latreille, 1802 | Crane Flies | 8719 | Species | Taxom |
| Tipulodictyidae Rohdendorf, 1962 | | 1 | Species | Taxom |
| Tipulopleciidae Rohdendorf, 1962 | | 1 | Species | Taxom |
| Trichoceridae Rondani, 1841 | Winter Crane Flies | 404 | Species | Taxom |
| Ulidiidae Macquart, 1835 | Picture-winged Flies | 51 | Species | Taxom |
| Uranorhagionidae Zhang, Yang ..., 2010 | | 5 | Species | Taxom |
| Valeseguyidae Amorim & Gri..., 2006 | | 1 | Species | Taxom |
| Vermileonidae Williston, 1886 | Wormlion | 25 | Species | Taxom |
| Vladipteridae Shcherbakov, 1995 | | 4 | Species | Taxom |
| Xenasteiidae Hardy, 1980 | | 4 | Species | Taxom |
| Xylomyidae Verrall, 1901 | Wood soldier flies | 122 | Species | Taxom |
| Xylophagidae Fallen, 1810 | Awl-flies | 125 | Species | Taxom |
| Zhangsolvidae Nagatomi & Yang, 1998 | | 5 | Species | Taxom |