The Hamamelidaceae are distinguishable from other families in the Saxifragales due to the range of floral characteristics that are generally uniform though all genera.

[5] The flowers of Hamamelidaceae are mostly bisexual with perianth parts, which mature to fruits arranged in spikes, racemes or nonglobose heads.

[10] This was clarified in 1998 by the molecular phylogenetic work of the Angiosperm Phylogeny Group (APG) which placed the family within the eudicot order Saxifragales.

[11] Peridiscaceae (4) Paeonia (Paeoniaceae) Liquidambar (Altingiaceae) Hamamelidaceae (27) Cercidiphyllum (Cercidiphyllaceae) Daphniphyllum (Daphniphyllaceae) Crassulaceae (34) Aphanopetalum (Aphanopetalaceae) Tetracarpaea (Tetracarpaeaceae) Penthorum (Penthoraceae) Haloragaceae s.s. (8) Iteaceae (including Pterostemonaceae) (2) Ribes (Grossulariaceae) Saxifragaceae (33) The infrafamilial classification of the Hamamelidaceae has been controversial, and has undergone a number of revisions based on morphology, the best known of which are those of Harms (1930)[10] and Endress (1989).

[5][14][15] Morphological and DNA studies have supported monophyly of the Hamamelidoideae[16][17] and have recognized the separation of the Rhodoleioideae and Disanthoideae subfamily and newly erected Mytilarioideae.

The subfamilies are Exbucklandioideae, Rhodoleioideae, Mytilarioideae, Disanthoideae, Hamamelidoideae, and Altingioideae, which has been elevated to a family Altingiaceae in some recent treatments.

The long-standing question of whether Altingioideae should be a separate family has been assessed and supported by morphological and molecular phylogenetic studies.

The revised structure has greatly reduced Hamamelideae to a monotypic taxon, which had previously been further divided into subtribes:[25] The Hamamelidaceae were widely distributed in the Northern Hemisphere during the Upper Cretaceous and early Tertiary.

Hamamelidaceae were obliterated from Europe along with numerous other genera of plants that were unable to escape the ice sheets due to geography (the Mediterranean Sea and Alps forming barriers that did not exist in North America and Asia)[26] The largest subfamily, the Hamamelidoideae, is now distributed in North America and western and eastern Asia.