De orde Gigartinales F.Schmitz kent 34 families.
| Acrotylaceae F.Schmitz | Dumontiaceae Bory | Phacelocarpaceae Searles |
| Areschougiaceae J.Agardh | Endocladiaceae Kylin | Phyllophoraceae Willkomm |
| Blinksiaceae Hollenberg & I.A.Abbott | Etheliaceae K.R.Dixon, C.W.Schneider & G.W.Saunders | Polyidaceae Kylin |
| Calosiphoniaceae Kylin | Furcellariaceae Greville | Ptilocladiopsaceae Rodriguez-Prieto, Freshwater & Hommersand |
| Caulacanthaceae Kützing | Gainiaceae R.L.Moe | Rhizophyllidaceae Ardissone |
| Chondriellaceae Levring | Gigartinaceae Bory | Rissoellaceae Kylin |
| Chondrymeniaceae Rodriguez-Prieto, G.Sartoni | Gloiosiphoniaceae Bory | Schmitziellaceae Guiry, Garbary & G.W.Saunders |
| Corynocystaceae Kraft | Haemeschariaceae Wilce & Maggs | Solieriaceae J.Agardh |
| Cruoriaceae Kylin | Kallymeniaceae Kylin | Sphaerococcaceae Dumortier |
| Cubiculosporaceae Kraft | Mychodeaceae Kylin | Tichocarpaceae Kylin |
| Cystocloniaceae Kützing | Mychodeophyllaceae Kraft | |
| Dicranemataceae Kylin | Nizymeniaceae Womersley |
