 George placed B. telmatiaea in subgenus Banksia because its inflorescence is a typical Banksia flower spike, section Oncostylis because it has hooked styles, and series Abietinae because its inflorescence is roughly spherical. He considered its closest relative to be B. leptophylla (Slender-leaved Banksia), which differs from B. telmatiaea in having longer leaves and larger flowers; yet in his arrangement he placed it between B. scabrella (Burma Road Banksia) and B. laricina (Rose-fruited Banksia).
