The electoral law allowed for parties and federations registered in the interior ministry, coalitions and groupings of electors to present lists of candidates.
Parties and federations intending to form a coalition ahead of an election were required to inform the relevant Electoral Commission within ten days of the election call, whereas groupings of electors needed to secure the signature of at least one percent of the electorate in the constituencies for which they sought election, disallowing electors from signing for more than one list of candidates.
Concurrently, parties, federations or coalitions that had not obtained a mandate in either chamber of the Cortes at the preceding election were required to secure the signature of at least 0.1 percent of electors in the aforementioned constituencies.

Below is a list of the main parties and electoral alliances which contested the election:
The Socialists' Party of Catalonia (PSC), Initiative for Catalonia Greens (ICV) and United and Alternative Left (EUiA) continued their Catalan Senate alliance without ERC, under the Agreement for Catalonia Progress name.
Concurrently, the new green Equo party allied itself with PSM–Nationalist Agreement (PSM–EN), Initiative Greens (IV) and Agreement for Majorca (ExM) in the Balearic Islands and with Sí Se Puede (SSP) and Socialists for Tenerife (SxTf) in the Santa Cruz de Tenerife constituency.
The electoral law allowed for parties and federations registered in the interior ministry, coalitions and groupings of electors to present lists of candidates. Parties and federations intending to form a coalition ahead of an election were required to inform the relevant Electoral Commission within ten days of the election call, whereas groupings of electors needed to secure the signature of at least one percent of the electorate in the constituencies for which they sought election, disallowing electors from signing for more than one list of candidates. Concurrently, parties, federations or coalitions that had not obtained a mandate in either chamber of the Cortes at the preceding election were required to secure the signature of at least 0.1 percent of electors in the aforementioned constituencies.
Below is a list of the main parties and electoral alliances which contested the election:
The Socialists' Party of Catalonia (PSC), Initiative for Catalonia Greens (ICV) and United and Alternative Left (EUiA) continued their Catalan Senate alliance without ERC, under the Agreement for Catalonia Progress name. Concurrently, the new green Equo party allied itself with PSM–Nationalist Agreement (PSM–EN), Initiative Greens (IV) and Agreement for Majorca (ExM) in the Balearic Islands and with Sí Se Puede (SSP) and Socialists for Tenerife (SxTf) in the Santa Cruz de Tenerife constituency.
2011 Spanish general election