The Hosho school of Yamato Province resided in Takaichi District and flourished from the late Kamakura period through the Nanbokucho era. Among the five Yamato traditions, the NBTHK regards its distinguishing characteristics as "the most conspicuously evident." Representative smiths include Sadamune and Sadayoshi, both said to have styled themselves "Hosho Goro," along with accomplished makers such as Sadakiyo, Sadaoki, and Sadamitsu, all sharing the character Sada (貞) as a common naming element. Dated works by Sadayoshi bearing era names from Bunpo, Genko, and Karyaku establish the school's chronological framework with considerable clarity. Though most surviving works are unsigned and greatly shortened, rare ubu-nakago tachi and tanto with higaki-yasurime constitute precious reference material for the school's identification.

The greatest hallmark of the Hosho school is the "fully developed masame forging pattern" that pervades the jitetsu from base to tip, with the masame-hada at the kissaki area running through and escaping into the mune. This grain is generally well-refined and tight, bearing thickly applied fine ji-nie that produces a characteristic urumi (moist, soft luster), with frequent fine chikei following the grain and a faint nie-utsuri standing up in many examples. The hamon is predominantly suguha-based, ranging from narrow suguha to chu-suguha with shallow notare tendency, often mixed with ko-gunome, ko-choji, or small gunome. Along the habuchi appear hotsure, kuichigai-ba, nijuba, uchi-noke, and yubashiri with particular frequency, while kinsuji and sunagashi run profusely throughout. The nie is consistently thick, bright, and clear. The boshi is characteristically straight, ending in yakizume with vigorous hakikake, and the tang is finished with higaki file marks and a blunt bukkiri tip.

The NBTHK repeatedly commends Hosho works for being "specimen-like" or "particularly exemplary reference pieces for the characteristic style of the Hosho school." Blades in sound condition are valued for their "abundant nikuoki" and a "weighty feeling overall" that lends them an air of "dignity and refinement." The school's jigane is frequently described as possessing an archaic taste, with a "bluish cast and lustrous quality" and the distinctive appearance of "black-tinged chikei in abundance." The vigorous internal activities along the edge and within the tempered zone, together with a bright and clear nioiguchi, are consistently identified as the school's principal points of interest. Among the Yamato traditions, the Hosho school's unmistakable masame character, reinforced by its signature tang construction, renders it one of the most immediately recognizable lineages in the Japanese sword canon.