Madrid is one of the 52 constituencies represented in the Congress of Deputies, the lower chamber of the Spanish parliament, the . The constituency (whose boundaries correspond to those of the homonymous province) currently elects 37 deputies. The electoral system uses the D'Hondt method and closed-list proportional voting, with a minimum threshold of three percent.

Electoral system The constituency was created as per the Political Reform Law and was first contested in the 1977 general election. The Law provided for the provinces of Spain to be established as multi-member districts in the Congress of Deputies,. with this regulation being maintained under the Spanish Constitution of 1978.. Additionally, the Constitution requires for any modification of the provincial limits to be approved under an organic law, needing an absolute majority in the Cortes Generales..

Voting is based on universal suffrage, comprising all Spanish nationals over 18 years of age with full political rights, provided that they have not been deprived of the right to vote by a final sentence.. The only exception was in 1977, when this was limited to nationals over 21 years of age and in full enjoyment of their political and civil rights.; . Amendments in 2011 required non-resident citizens to apply for voting, a system known as "begged" voting ().. which was abolished in 2022. Further, amendments in 2018 granted the right to vote to those legally incapacitated. The Congress of Deputies has a minimum of 300 and a maximum of 400 seats, with electoral provisions fixing its size at 350. Of these, 348 are elected in 50 multi-member constituencies corresponding to the provinces of Spain—each of which is assigned an initial minimum of two seats and the remaining 248 distributed in proportion to population—using the D'Hondt method and closed-list proportional voting, with a three percent-threshold of valid votes (including blank ballots) in each constituency. The remaining two seats are allocated to Ceuta and Melilla as single-member districts elected by plurality voting.; ; ; . The use of this electoral method may result in a higher effective threshold depending on district magnitude and vote distribution. The law does not provide for by-elections to fill vacant seats; instead, any vacancies arising after the proclamation of candidates and during the legislative term are filled by the next candidates on the party lists or, when required, by designated substitutes.; .

The electoral law allows for parties and federations registered in the interior ministry, alliances and groupings of electors to present lists of candidates. Parties and federations intending to form an alliance are required to inform the relevant electoral commission within 10 days of the election call—15 before 1985—whereas groupings of electors need to secure the signature of at least one percent of the electorate in the constituencies for which they seek election—one permille of the electorate, with a compulsory minimum of 500 signatures, until 1985—disallowing electors from signing for more than one list. Also since 2011, parties, federations or alliances that have not obtained a mandate in either chamber of the at the preceding election are required to secure the signature of at least 0.1 percent of electors in the aforementioned constituencies.; . Amendments in 2007 required a balanced composition of men and women in the electoral lists, so that candidates of either sex made up at least 40 percent of the total composition; further amendments in 2024 required the use of a zipper system..

Deputies Deputies 1977–present Legislature Election Distribution Constituent 1977 4 3 11 11 3 1st 1979 4 12 12 3 1 2nd 1982 1 18 1 1 11 3rd 1986 2 15 5 11 4th 1989 5 12 4 12 5th 1993 5 13 16 6th 1996 6 11 17 7th 2000 3 12 19 8th 2004 2 16 17 9th 2008 1 15 1 18 10th 2011 3 10 4 19 11th 2015 2 8 6 7 13 12th 2016 8 7 6 15 13th 2019 (Apr) 6 11 8 7 5 14th 2019 (Nov) 5 2 10 3 10 7 15th 2023 6 10 16 5

General elections 2023 + Summary of the 23 July 2023 Congress of Deputies election results in Madrid Parties and alliances Popular vote Seats Votes % ±pp Total +/− People's Party (PP) 1,463,183 40.55 +15.64 16 +6 Spanish Socialist Workers' Party (PSOE) 1,004,599 27.84 +0.97 10 ±0 Unite (Sumar)1 557,780 15.46 –3.20 6 –1 Vox (Vox) 506,164 14.03 –4.31 5 –2 Animalist Party with the Environment (PACMA)2 21,742 0.60 –0.30 0 ±0 Workers' Front (FO) 7,652 0.21 New 0 ±0 For a Fairer World (PUM+J) 6,749 0.19 +0.07 0 ±0 Zero Cuts (Recortes Cero) 3,784 0.10 –0.04 0 ±0 Communist Party of the Workers of Spain (PCTE) 3,407 0.09 +0.04 0 ±0 Humanist Party (PH) 2,902 0.08 +0.01 0 ±0 Spanish Phalanx of the CNSO (FE de las JONS) 1,751 0.05 New 0 ±0 Citizens–Party of the Citizenry (Cs) n/a n/a –9.07 0 –3 Blank ballots 28,960 0.80 –0.01 Total 3,608,673 37 ±0 Valid votes 3,608,673 99.15 –0.06 Invalid votes 30,827 0.85 +0.06 Votes cast / turnout 3,639,500 69.66 –0.93 Abstentions 1,585,061 30.34 +0.93 Registered voters 5,224,561 Sources

November 2019 + Summary of the 10 November 2019 Congress of Deputies election results in Madrid Parties and alliances Popular vote Seats Votes % ±pp Total +/− Spanish Socialist Workers' Party (PSOE) 957,401 26.87 –0.40 10 –1 People's Party (PP) 887,474 24.91 +6.27 10 +3 Vox (Vox) 653,476 18.34 +4.48 7 +2 United We Can (Podemos–IU) 463,629 13.01 –3.22 5 –1 Citizens–Party of the Citizenry (Cs) 323,076 9.07 –11.88 3 –5 More Country–Equo (Más País–Equo) 201,389 5.65 New 2 +2 Animalist Party Against Mistreatment of Animals (PACMA) 31,983 0.90 –0.45 0 ±0 Zero Cuts–Green Group–PCAS–TC (Recortes Cero–GV–PCAS–TC) 5,129 0.14 –0.06 0 ±0 For a Fairer World (PUM+J) 4,305 0.12 –0.02 0 ±0 Humanist Party (PH) 2,508 0.07 –0.02 0 ±0 Communist Party of the Peoples of Spain (PCPE) 2,099 0.06 +0.01 0 ±0 Communist Party of the Workers of Spain (PCTE) 1,895 0.05 –0.01 0 ±0 Blank ballots 28,783 0.81 +0.16 Total 3,563,147 37 ±0 Valid votes 3,563,147 99.21 +0.05 Invalid votes 28,317 0.79 –0.05 Votes cast / turnout 3,591,464 70.59 –4.87 Abstentions 1,496,629 29.41 +4.87 Registered voters 5,088,093 Sources

April 2019 + Summary of the 28 April 2019 Congress of Deputies election results in Madrid Parties and alliances Popular vote Seats Votes % ±pp Total +/− Spanish Socialist Workers' Party (PSOE) 1,031,534 27.27 +7.70 11 +4 Citizens–Party of the Citizenry (Cs) 792,203 20.95 +3.16 8 +2 People's Party (PP) 705,119 18.64 –19.61 7 –8 United We Can (Podemos–IU–Equo) 613,911 16.23 –5.06 6 –2 Vox (Vox) 524,176 13.86 +13.38 5 +5 Animalist Party Against Mistreatment of Animals (PACMA) 50,909 1.35 +0.22 0 ±0 Act (PACT) 19,208 0.51 New 0 ±0 Zero Cuts–Green Group–PCAS–TC (Recortes Cero–GV–PCAS–TC) 7,512 0.20 –0.01 0 ±0 For a Fairer World (PUM+J) 5,221 0.14 New 0 ±0 Humanist Party (PH) 3,456 0.09 +0.03 0 ±0 Communist Party of the Workers of Spain (PCTE) 2,329 0.06 New 0 ±0 Communist Party of the Peoples of Spain (PCPE) 2,038 0.05 –0.04 0 ±0 Blank ballots 24,631 0.65 +0.13 Total 3,782,247 37 +1 Valid votes 3,782,247 99.16 –0.16 Invalid votes 32,112 0.84 +0.16 Votes cast / turnout 3,814,359 75.46 +4.65 Abstentions 1,240,596 24.54 –4.65 Registered voters 5,054,955 Sources

2016 + Summary of the 26 June 2016 Congress of Deputies election results in Madrid Parties and alliances Popular vote Seats Votes % ±pp Total +/− People's Party (PP) 1,325,665 38.25 +4.81 15 +2 United We Can (Podemos–IU–Equo–CLI–AS)1 737,885 21.29 –4.95 8 –2 Spanish Socialist Workers' Party (PSOE) 678,340 19.57 +1.73 7 +1 Citizens–Party of the Citizenry (C's) 616,503 17.79 –1.03 6 –1 Animalist Party Against Mistreatment of Animals (PACMA) 39,117 1.13 +0.35 0 ±0 Vox (Vox) 16,803 0.48 –0.15 0 ±0 Union, Progress and Democracy (UPyD) 14,659 0.42 –0.78 0 ±0 Zero Cuts–Green Group (Recortes Cero–GV) 7,377 0.21 +0.10 0 ±0 Spanish Phalanx of the CNSO (FE de las JONS) 3,946 0.11 –0.02 0 ±0 Communist Party of the Peoples of Spain (PCPE) 3,110 0.09 +0.04 0 ±0 Humanist Party (PH) 2,148 0.06 +0.01 0 ±0 Libertarian Party (P–LIB) 1,111 0.03 ±0.00 0 ±0 Internationalist Solidarity and Self-Management (SAIn) 994 0.03 ±0.00 0 ±0 Blank ballots 18,137 0.52 ±0.00 Total 3,465,795 36 ±0 Valid votes 3,465,795 99.32 –0.04 Invalid votes 23,581 0.68 +0.04 Votes cast / turnout 3,489,376 70.81 –3.31 Abstentions 1,438,556 29.19 +3.31 Registered voters 4,927,932 Sources

2015 + Summary of the 20 December 2015 Congress of Deputies election results in Madrid Parties and alliances Popular vote Seats Votes % ±pp Total +/− People's Party (PP) 1,210,219 33.44 –17.53 13 –6 We Can (Podemos) 756,257 20.90 New 8 +8 Citizens–Party of the Citizenry (C's) 681,167 18.82 New 7 +7 Spanish Socialist Workers' Party (PSOE) 645,645 17.84 –8.21 6 –4 United Left–Popular Unity in Common (IU–UPeC) 190,193 5.26 –2.78 2 –1 Union, Progress and Democracy (UPyD) 43,508 1.20 –9.10 0 –4 Animalist Party Against Mistreatment of Animals (PACMA) 28,322 0.78 +0.39 0 ±0 Vox (Vox) 22,643 0.63 New 0 ±0 For the Left–The Greens (X Izda) 4,994 0.14 New 0 ±0 Spanish Phalanx of the CNSO (FE de las JONS) 4,579 0.13 New 0 ±0 Zero Cuts–Green Group (Recortes Cero–GV) 4,037 0.11 New 0 ±0 For a Fairer World (PUM+J) 2,870 0.08 –0.08 0 ±0 Humanist Party (PH) 1,779 0.05 –0.03 0 ±0 Communist Party of the Peoples of Spain (PCPE) 1,742 0.05 –0.06 0 ±0 Internationalist Solidarity and Self-Management (SAIn) 1,137 0.03 –0.01 0 ±0 Libertarian Party (P–LIB) 1,075 0.03 –0.02 0 ±0 Blank ballots 18,751 0.52 –0.52 Total 3,618,918 36 ±0 Valid votes 3,618,918 99.36 +0.40 Invalid votes 23,209 0.64 –0.40 Votes cast / turnout 3,642,127 74.12 +0.86 Abstentions 1,271,766 25.88 –0.86 Registered voters 4,913,893 Sources

2011 + Summary of the 20 November 2011 Congress of Deputies election results in Madrid Parties and alliances Popular vote Seats Votes % ±pp Total +/− People's Party (PP) 1,719,709 50.97 +1.78 19 +1 Spanish Socialist Workers' Party (PSOE) 878,724 26.05 –13.63 10 –5 Union, Progress and Democracy (UPyD) 347,354 10.30 +6.56 4 +3 United Left–The Greens: Plural Left (IU–LV) 271,209 8.04 +3.38 3 +2 Equo (Equo) 65,169 1.93 New 0 ±0 Animalist Party Against Mistreatment of Animals (PACMA) 13,136 0.39 +0.26 0 ±0 Blank Seats (EB) 12,877 0.38 New 0 ±0 Asturias Forum (FAC) 6,645 0.20 New 0 ±0 For a Fairer World (PUM+J) 5,314 0.16 +0.09 0 ±0 Anti-capitalists (Anticapitalistas) 4,268 0.13 New 0 ±0 Communist Party of the Peoples of Spain (PCPE) 3,815 0.11 +0.05 0 ±0 Humanist Party (PH) 2,706 0.08 –0.05 0 ±0 Republicans (RPS) 2,183 0.06 New 0 ±0 Internationalist Socialist Workers' Party (POSI) 1,723 0.05 +0.01 0 ±0 Individual Freedom Party (P–LIB) 1,655 0.05 New 0 ±0 Internationalist Solidarity and Self-Management (SAIn) 1,350 0.04 +0.03 0 ±0 Communist Unification of Spain (UCE) 875 0.03 New 0 ±0 Blank ballots 35,093 1.04 +0.09 Total 3,373,805 36 +1 Valid votes 3,373,805 98.96 –0.52 Invalid votes 35,526 1.04 +0.52 Votes cast / turnout 3,409,331 73.26 –5.82 Abstentions 1,244,448 26.74 +5.82 Registered voters 4,653,779 Sources

2008