Banksia subg. Banksia is a valid botanic name for a subgenus of Banksia. As an autonym, it necessarily contains the type species of Banksia, B. serrata (saw banksia). Within this constraint, however, there have been various circumscriptions.

B. subg. Banksia can be traced back to Banksia verae, an unranked taxon published by Robert Brown in his 1810 Prodromus Florae Novae Hollandiae et Insulae Van Diemen. Under Brown's arrangement, Banksia was divided into two groups based on inflorescence shape. Banksia verae was defined as containing those Banksia taxa with the elongate flower spike typical of Banksia, and it thus contained all but one species. The remaining species, B. ilicifolia (Holly-leaved Banksia), has a dome-shaped head and so was placed alone in Isostylis.

Brown published a further eleven species in 1830, placing all of them in Banksia verae. The 1830 circumscription of Banksia verae was as follows:

Banksia verae was renamed Eubanksia by Stephan Endlicher in his 1847 fourth supplement to Genera Plantarum Secundum Ordines Naturales Disposita, and this name was retained in Carl Meissner's 1856 arrangement. Meissner gave Eubanksia sectional rank, further dividing it into four series, B. ser. Abietinæ, B. ser. Salicinae, B. ser. Quercinae and B. ser. Dryandroideae. These series were defined in terms of leaf shape alone, and were hence all highly heterogeneous, with the exception of B. ser. Abietinæ, which contained only (but not all) species with hooked styles.

Meissner's 1856 circumscription of B. sect. Eubanksia was as follows:

The top-level split into Eubanksia and Isostylis was abandoned by George Bentham in 1870. Instead, Bentham divided the genus into five section, retaining B. sect. Isostylis, but dividing the remaining species into four sections.

In 1981, Alex George published a thorough revision of Banksia in his classic monograph The genus Banksia L.f. (Proteaceae). George reinstated Meissner's Eubanksia and Isostylis, giving them subgeneric rank. By this time, however, the rules of botanical nomenclature had been formalised in such a way that Eubanksia was required to take the autonym B. subg. Banksia.

George's arrangement was overturned in 1996 by Kevin Thiele and Pauline Ladiges, but in 1999 George published a slightly modified version in his treatment of Banksia for the Flora of Australia series of monographs. George's 1999 arrangement is not universally accepted, and accords poorly with recently published cladistic analyses, yet it remains the most recently published arrangement.