The 2012–13 Segunda División B season was the 36th since its establishment. The first matches of the season were played on 26 August 2012, and the league phase ended on 19 May 2013. The entire season ended on 30 June 2013 with the promotion play-off finals.

Summary before 2012–13 season

Playoffs de Ascenso: * Real Madrid Castilla (P) *

CD Tenerife Club Deportivo Tenerife, S.A.D. is a Spanish football club based in Santa Cruz de Tenerife, Tenerife, in the Canary Islands. Founded in 1922, the club plays in the Segunda División, holding home matches at the Estadio Heliodoro Rodríguez L� ...

CD Lugo Club Deportivo Lugo is a List of football clubs in Spain, Spanish football team based in Lugo, in the autonomous community of Galicia (Spain), Galicia. Founded on 8 July 1953, it plays in Primera Federación, holding home games at ''Estadio Anxo ...

(P) *

Albacete Balompié Albacete Balompié is a List of football clubs in Spain, Spanish football team based in Albacete, in the autonomous community of Castile–La Mancha. Founded on 5 July 1939, it currently plays in Segunda División, the second tier of Spanish foo ...

* CD Mirandés (P) *

SD Ponferradina Sociedad Deportiva Ponferradina, S.A.D. is a Spanish football team based in Ponferrada, in the El Bierzo region, in the autonomous community of Castile and León. Founded on 7 June 1922, it plays in Primera Federación - Group 1, holding home ma ...

(P) * SD Eibar * SD Amorebieta * CD Atlético Baleares * Orihuela CF * Huracán CF * CF Badalona * Cádiz CF * Real Balompédica Linense * Lucena CF *

Real Jaén Real Jaén Club de Fútbol, S.A.D. is a List of football clubs in Spain, Spanish football team based in Jaén, Spain, Jaén, in the autonomous community of Andalusia. Founded in 1929 it plays in , holding home matches at ''Nuevo Estadio de La Vict ...

Relegated from

Segunda División The Campeonato Nacional de Liga de Segunda División, commonly known as Segunda División or La Liga 2, and officially known as LaLiga HyperMotion for sponsorship reasons, is the men's second professional association football division of the Spa ...

: * Villarreal CF B * CD Alcoyano *

FC Cartagena Fútbol Club Cartagena, S.A.D. is a Spanish football team based in Cartagena, in the Region of Murcia, Spain. Founded in 1995 it currently plays in Segunda División, holding home games at '' Estadio Cartagonova'', with a capacity of 15,105 sp ...

Gimnàstic de Tarragona Club Gimnàstic de Tarragona, commonly known as Gimnàstic Tarragona or sometimes just Nàstic, is a Spanish sports club based in Tarragona, in the autonomous community of Catalonia. Its football team plays in . The club was founded in 1886 an ...

Promoted from

Tercera División Tercera División () was the fourth tier of the Spanish football league system. Until 1977, it was the third tier of the Spanish football league system. Founded in 1929, it was below the ''Primera División'' (also known as La Liga), the ''Segund ...

: *

CD Ourense Club Deportivo Ourense, S.A.D. was a Spanish football team based in Ourense, in the autonomous community of Galicia. Founded in 1952 after the dissolution of old UD Orensana, it played in Segunda División B – Group 1, holding home games a ...

(from

Group 1 Group 1 may refer to: * Alkali metal, a chemical element classification for Alkali metal * Group 1 (motorsport), a regulation set of the FIA for series-production touring cars used in motorsport. * Group One Thoroughbred horse races, the leading e ...

) * Caudal Deportivo (from

Group 2 The term Group 2 may refer to: * Alkaline earth metal The alkaline earth metals are six chemical elements in group (periodic table), group 2 of the periodic table. They are beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (B ...

) * SD Noja (from

Group 3 Group 3 may refer to: * Group 3 element, chemical element classification * Group 3 (motorsport), FIA classification of cars used in auto racing and rallying * Group 3, the third tier of races in worldwide Thoroughbred horse racing * Group 3 image ...

) * AE Prat (from

Group 5 Group 5 may refer to: * Group 5 element, chemical element classification * Group 5 (motorsport), FIA classification for cars in auto racing See also * G5 (disambiguation) {{Disambig ...

) * Loja CD (from

Group 9 Group 9 may refer to: * Group 9 element * Group 9 Rugby League *"Group 9", Australian arts collective, whose members included John Dowie {{disambig