Founded as San Sebastián Club de Fútbol, Real Sociedad's B team first reached the second division nine years later. In the 1961–62 campaign, it achieved its best ever classification in the category after finishing fifth; however, as the main squad was relegated in La Liga, it was ineligible for promotion, being relegated instead. In 1980 Real Sociedad B was promoted to the newly created Segunda División B, remaining in that category 17 consecutive seasons. Afterwards it fluctuated between divisions three and four, reaching the promotion playoffs of the former division in 1991 and 2006 but subsequently falling short. In 1992, a change in rules forced the team to change its name, and it was renamed Real Sociedad de Fútbol B. Liga de Fútbol Profesional's rules prohibit B clubs from having different names from their parent club, the exceptions being Real Madrid Castilla and Sevilla Atlético. A change in the club structure from 2016 means that most Sanse players will be promoted from a new subsidiary, Real Sociedad C, who will play in Tercera División with under-20 graduates of the club's youth system. The Real Sociedad C team must play at least one division below Sanse. In the 2017-18 season the club won bronze medals of the Segunda División B, group 2.
Club names
San Sebastián Club de Fútbol – '
Real Sociedad de Fútbol B – '
Season to season
As an independent club
As the reserve team of Real Sociedad
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2 seasons in Segunda División
34 seasons in Segunda División B
27 seasons in Tercera División
Current squad
Honours
Tercera División:
Stadium
Real Sociedad B hold home games at Instalaciones de Zubieta, which holds 2,500 spectators. Players of both the first and the second teams train in these facilities, with Sanse's players being nicknamed "Potrillos" as the grounds are located near the city's horse racetrack.
