# Biscay (Congress of Deputies constituency)

Biscay (Basque: Bizkaia, Spanish: Vizcaya) is one of the 52 constituencies (Spanish: circunscripciones) represented in the Congress of Deputies, the lower chamber of the Spanish parliament, the Cortes Generales. The constituency currently elects eight deputies. Its boundaries correspond to those of the Spanish province of Biscay. The electoral system uses the D'Hondt method and a closed-list proportional representation, with a minimum threshold of three percent.

## Electoral system

The constituency was created as per the Political Reform Act 1977 and was first contested in the 1977 general election. The Act 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 on the basis of universal suffrage, which comprises all nationals over 18 years of age and in full enjoyment of their political rights. 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 to the electoral law in 2011 required for Spaniards abroad to apply for voting before being permitted to vote, a system known as "begged" or expat vote (Spanish: Voto rogado), which was abolished in 2022. 348 seats are elected using the D'Hondt method and a closed list proportional representation, with an electoral threshold of three percent of valid votes—which includes blank ballots—being applied in each constituency. Each provincial constituency is entitled to an initial minimum of two seats, with the remaining 248 being distributed in proportion to their populations. Ceuta and Melilla are allocated the two remaining seats, which are elected using plurality voting. The use of the electoral method may result in an effective threshold based on the district magnitude and the distribution of votes among candidacies.
The electoral law allows 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 are required to inform the relevant Electoral Commission within ten days of the election call—fifteen 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 of candidates. Also since 2011, parties, federations or coalitions that have not obtained a mandate in either chamber of the Cortes at the preceding election are required to secure the signature of at least 0.1 percent of electors in the aforementioned constituencies.

## Deputies

Deputies 1977–present :
| Key to parties  HB  Amaiur  EH Bildu  EH Bildu  IU  U.Podemos  Podemos  Sumar  EE  PSOE  EA  PNV  UCD  PP  CP  AP |||
| Legislature | Election | Distribution |
| Constituent | 1977 | 3 4 2 1 |
| 1st | 1979 | 2 2 4 2 |
| 2nd | 1982 | 1 4 4 1 |
| 3rd | 1986 | 2 1 3 3 1 |
| 4th | 1989 | 2 1 2 1 3 1 |
| 5th | 1993 | 1 3 3 2 |
| 6th | 1996 | 1 1 2 3 2 |
| 7th | 2000 | 2 4 3 |
| 8th | 2004 | 3 4 2 |
| 9th | 2008 | 4 3 1 |
| 10th | 2011 | 2 2 3 1 |
| 11th | 2015 | 1 2 1 3 1 |
| 12th | 2016 | 1 3 1 2 1 |
| 13th | 2019 (Apr) | 1 2 2 3 |
| 14th | 2019 (Nov) | 1 1 2 3 1 |
| 15th | 2023 | 2 1 2 2 1 |

## Elections
### 2023 general election

Summary of the 23 July 2023 Congress of Deputies election results in Biscay :
| Parties and alliances | Parties and alliances | Popular vote | Popular vote | Popular vote | Seats | Seats |
| Parties and alliances | Parties and alliances | Votes | % | ±pp | Total | +/− |
| | Basque Nationalist Party (EAJ/PNV) | 164,188 | 26.93 | –8.29 | 2 | –1 |
| | Socialist Party of the Basque Country–Basque Country Left (PSE–EE (PSOE)) | 157,448 | 25.82 | +6.69 | 2 | ±0 |
| | Basque Country Gather (EH Bildu) | 125,867 | 20.64 | +5.62 | 2 | +1 |
| | People's Party (PP) | 70,533 | 11.57 | +2.75 | 1 | ±0 |
| | Unite (Sumar)$^1$ | 66,592 | 10.92 | –5.85 | 1 | ±0 |
| | Vox (Vox) | 16,069 | 2.64 | +0.22 | 0 | ±0 |
| | Animalist Party with the Environment (PACMA)$^2$ | 2,729 | 0.45 | –0.15 | 0 | ±0 |
| | Workers' Front (FO) | 929 | 0.15 | New | 0 | ±0 |
| | For a Fairer World (PUM+J) | 804 | 0.13 | +0.05 | 0 | ±0 |
| | Communist Party of the Workers of the Basque Country (PCTE/ELAK) | 618 | 0.10 | +0.02 | 0 | ±0 |
| | Zero Cuts (Recortes Cero) | 525 | 0.09 | –0.03 | 0 | ±0 |
| Blank ballots | Blank ballots | 3,391 | 0.56 | –0.04 | | |
| Total | Total | 609,693 | | | 8 | ±0 |
| Valid votes | Valid votes | 609,693 | 99.15 | –0.27 | | |
| Invalid votes | Invalid votes | 5,251 | 0.85 | +0.27 | | |
| Votes cast / turnout | Votes cast / turnout | 614,944 | 65.21 | –1.55 | | |
| Abstentions | Abstentions | 328,039 | 34.79 | +1.55 | | |
| Registered voters | Registered voters | 942,983 | | | | |
| Sources |||||||
| Footnotes: $^1$ Unite results are compared to the combined totals of United We Can and More Country–Ecologist Candidacy in the November 2019 election.$^2$ Animalist Party with the Environment results are compared to Animalist Party Against Mistreatment of Animals totals in the November 2019 election. |||||||

### November 2019 general election

Summary of the 10 November 2019 Congress of Deputies election results in Biscay :
| Parties and alliances | Parties and alliances | Popular vote | Popular vote | Popular vote | Seats | Seats |
| Parties and alliances | Parties and alliances | Votes | % | ±pp | Total | +/− |
| | Basque Nationalist Party (EAJ/PNV) | 221,979 | 35.22 | +0.88 | 3 | ±0 |
| | Socialist Party of the Basque Country–Basque Country Left (PSE–EE (PSOE)) | 120,566 | 19.13 | –0.75 | 2 | ±0 |
| | United We Can (Podemos–IU) | 97,125 | 15.41 | –2.31 | 1 | –1 |
| | Basque Country Gather (EH Bildu) | 94,669 | 15.02 | +1.66 | 1 | ±0 |
| | People's Party (PP) | 55,621 | 8.82 | +1.56 | 1 | +1 |
| | Vox (Vox) | 15,284 | 2.42 | +0.11 | 0 | ±0 |
| | More Country–Ecologist Candidacy (Más País–Candidatura Ecologista) | 8,542 | 1.36 | New | 0 | ±0 |
| | Citizens–Party of the Citizenry (Cs) | 6,929 | 1.10 | –2.01 | 0 | ±0 |
| | Animalist Party Against Mistreatment of Animals (PACMA) | 3,783 | 0.60 | –0.30 | 0 | ±0 |
| | Zero Cuts–Green Group (Recortes Cero–GV) | 753 | 0.12 | –0.05 | 0 | ±0 |
| | For a Fairer World (PUM+J) | 494 | 0.08 | –0.04 | 0 | ±0 |
| | Communist Party of the Workers of the Basque Country (PCTE/ELAK) | 491 | 0.08 | –0.01 | 0 | ±0 |
| | European Solidarity Action Party (Solidaria) | 270 | 0.04 | –0.04 | 0 | ±0 |
| Blank ballots | Blank ballots | 3,806 | 0.60 | –0.06 | | |
| Total | Total | 630,312 | | | 8 | ±0 |
| Valid votes | Valid votes | 630,312 | 99.42 | +0.11 | | |
| Invalid votes | Invalid votes | 3,665 | 0.58 | –0.11 | | |
| Votes cast / turnout | Votes cast / turnout | 633,977 | 66.76 | –6.09 | | |
| Abstentions | Abstentions | 315,621 | 33.24 | +6.09 | | |
| Registered voters | Registered voters | 949,598 | | | | |
| Sources |||||||

### April 2019 general election

Summary of the 28 April 2019 Congress of Deputies election results in Biscay :
| Parties and alliances | Parties and alliances | Popular vote | Popular vote | Popular vote | Seats | Seats |
| Parties and alliances | Parties and alliances | Votes | % | ±pp | Total | +/− |
| | Basque Nationalist Party (EAJ/PNV) | 235,916 | 34.34 | +6.12 | 3 | +1 |
| | Socialist Party of the Basque Country–Basque Country Left (PSE–EE (PSOE)) | 136,547 | 19.88 | +5.97 | 2 | +1 |
| | United We Can (Podemos–IU–Equo Berdeak) | 121,740 | 17.72 | –11.15 | 2 | –1 |
| | Basque Country Gather (EH Bildu) | 91,771 | 13.36 | +2.47 | 1 | ±0 |
| | People's Party (PP) | 49,859 | 7.26 | –5.45 | 0 | –1 |
| | Citizens–Party of the Citizenry (Cs) | 21,392 | 3.11 | –0.22 | 0 | ±0 |
| | Vox (Vox) | 15,839 | 2.31 | +2.21 | 0 | ±0 |
| | Animalist Party Against Mistreatment of Animals (PACMA) | 6,187 | 0.90 | +0.12 | 0 | ±0 |
| | Zero Cuts–Green Group (Recortes Cero–GV) | 1,177 | 0.17 | –0.02 | 0 | ±0 |
| | For a Fairer World (PUM+J) | 844 | 0.12 | New | 0 | ±0 |
| | Communist Party of the Workers of the Basque Country (PCTE/ELAK) | 603 | 0.09 | New | 0 | ±0 |
| | European Solidarity Action Party (Solidaria) | 528 | 0.08 | New | 0 | ±0 |
| Blank ballots | Blank ballots | 4,557 | 0.66 | +0.03 | | |
| Total | Total | 686,960 | | | 8 | ±0 |
| Valid votes | Valid votes | 686,960 | 99.31 | –0.01 | | |
| Invalid votes | Invalid votes | 4,742 | 0.69 | +0.01 | | |
| Votes cast / turnout | Votes cast / turnout | 691,702 | 72.85 | +6.88 | | |
| Abstentions | Abstentions | 257,740 | 27.15 | –6.88 | | |
| Registered voters | Registered voters | 949,442 | | | | |
| Sources |||||||

### 2016 general election

Summary of the 26 June 2016 Congress of Deputies election results in Biscay :
| Parties and alliances | Parties and alliances | Popular vote | Popular vote | Popular vote | Seats | Seats |
| Parties and alliances | Parties and alliances | Votes | % | ±pp | Total | +/− |
| | United We Can (Podemos/Ahal Dugu–IU–Equo)$^1$ | 179,347 | 28.87 | –0.05 | 3 | +1 |
| | Basque Nationalist Party (EAJ/PNV) | 175,296 | 28.22 | +0.31 | 2 | –1 |
| | Socialist Party of the Basque Country–Basque Country Left (PSE–EE (PSOE)) | 86,425 | 13.91 | +0.93 | 1 | ±0 |
| | People's Party (PP) | 78,965 | 12.71 | +1.31 | 1 | ±0 |
| | Basque Country Gather (EH Bildu) | 67,653 | 10.89 | –1.60 | 1 | ±0 |
| | Citizens–Party of the Citizenry (C's) | 20,685 | 3.33 | –0.51 | 0 | ±0 |
| | Animalist Party Against Mistreatment of Animals (PACMA) | 4,865 | 0.78 | +0.12 | 0 | ±0 |
| | Zero Cuts–Green Group (Recortes Cero–GV) | 1,176 | 0.19 | +0.02 | 0 | ±0 |
| | Blank Seats (EB/AZ) | 1,026 | 0.17 | +0.01 | 0 | ±0 |
| | Union, Progress and Democracy (UPyD) | 766 | 0.12 | –0.19 | 0 | ±0 |
| | Vox (Vox) | 641 | 0.10 | New | 0 | ±0 |
| | Communist Party of the Peoples of Spain (PCPE) | 467 | 0.08 | +0.02 | 0 | ±0 |
| Blank ballots | Blank ballots | 3,907 | 0.63 | –0.11 | | |
| Total | Total | 621,219 | | | 8 | ±0 |
| Valid votes | Valid votes | 621,219 | 98.32 | +0.03 | | |
| Invalid votes | Invalid votes | 4,225 | 0.68 | –0.03 | | |
| Votes cast / turnout | Votes cast / turnout | 625,444 | 65.97 | –3.44 | | |
| Abstentions | Abstentions | 322,636 | 34.03 | +3.44 | | |
| Registered voters | Registered voters | 948,080 | | | | |
| Sources |||||||
| Footnotes: $^1$ United We Can results are compared to the combined totals of We Can and United Left–Popular Unity in Common in the 2015 election. |||||||

### 2015 general election

Summary of the 20 December 2015 Congress of Deputies election results in Biscay :
| Parties and alliances | Parties and alliances | Popular vote | Popular vote | Popular vote | Seats | Seats |
| Parties and alliances | Parties and alliances | Votes | % | ±pp | Total | +/− |
| | Basque Nationalist Party (EAJ/PNV) | 182,604 | 27.91 | –4.70 | 3 | ±0 |
| | We Can (Podemos/Ahal Dugu) | 170,728 | 26.10 | New | 2 | +2 |
| | Socialist Party of the Basque Country–Basque Country Left (PSE–EE (PSOE)) | 84,893 | 12.98 | –8.41 | 1 | –1 |
| | Basque Country Gather (EH Bildu)$^1$ | 81,704 | 12.49 | –6.70 | 1 | –1 |
| | People's Party (PP) | 74,560 | 11.40 | –6.32 | 1 | ±0 |
| | Citizens–Party of the Citizenry (C's) | 25,148 | 3.84 | New | 0 | ±0 |
| | United Left–Popular Unity in Common (IU–UPeC) | 18,466 | 2.82 | –0.96 | 0 | ±0 |
| | Animalist Party Against Mistreatment of Animals (PACMA) | 4,342 | 0.66 | +0.15 | 0 | ±0 |
| | Union, Progress and Democracy (UPyD) | 2,012 | 0.31 | –1.39 | 0 | ±0 |
| | Left–For the Left (Ezkerra) | 1,447 | 0.22 | New | 0 | ±0 |
| | Zero Cuts–Green Group (Recortes Cero–GV) | 1,089 | 0.17 | New | 0 | ±0 |
| | Blank Seats (EB/AZ) | 1,045 | 0.16 | –0.29 | 0 | ±0 |
| | For a Fairer World (PUM+J) | 479 | 0.07 | –0.19 | 0 | ±0 |
| | Communist Party of the Peoples of Spain (PCPE) | 414 | 0.06 | New | 0 | ±0 |
| | Social Justice, Citizen Participation (JS,PC) | 406 | 0.06 | New | 0 | ±0 |
| Blank ballots | Blank ballots | 4,840 | 0.74 | –0.40 | | |
| Total | Total | 654,177 | | | 8 | ±0 |
| Valid votes | Valid votes | 654,177 | 99.29 | +0.30 | | |
| Invalid votes | Invalid votes | 4,647 | 0.71 | –0.30 | | |
| Votes cast / turnout | Votes cast / turnout | 658,824 | 69.41 | +1.33 | | |
| Abstentions | Abstentions | 290,353 | 30.59 | –1.33 | | |
| Registered voters | Registered voters | 949,177 | | | | |
| Sources |||||||
| Footnotes: $^1$ Basque Country Gather results are compared to Amaiur totals in the 2011 election. |||||||

### 2011 general election

Summary of the 20 November 2011 Congress of Deputies election results in Biscay :
| Parties and alliances | Parties and alliances | Popular vote | Popular vote | Popular vote | Seats | Seats |
| Parties and alliances | Parties and alliances | Votes | % | ±pp | Total | +/− |
| | Basque Nationalist Party (EAJ/PNV) | 208,683 | 32.61 | +1.51 | 3 | ±0 |
| | Socialist Party of the Basque Country–Basque Country Left (PSE–EE (PSOE)) | 136,853 | 21.39 | –15.60 | 2 | –2 |
| | Amaiur (Amaiur)$^1$ | 122,796 | 19.19 | +14.54 | 2 | +2 |
| | People's Party (PP) | 113,401 | 17.72 | –0.68 | 1 | ±0 |
| | United Left–The Greens: Plural Left (IU–LV) | 24,205 | 3.78 | –0.57 | 0 | ±0 |
| | Union, Progress and Democracy (UPyD) | 10,886 | 1.70 | +0.75 | 0 | ±0 |
| | Equo (Equo) | 7,387 | 1.15 | New | 0 | ±0 |
| | Animalist Party Against Mistreatment of Animals (PACMA) | 3,278 | 0.51 | +0.14 | 0 | ±0 |
| | Blank Seats (EB) | 2,886 | 0.45 | New | 0 | ±0 |
| | For a Fairer World (PUM+J) | 1,670 | 0.26 | +0.03 | 0 | ±0 |
| | Communist Unification of Spain (UCE) | 550 | 0.09 | New | 0 | ±0 |
| Blank ballots | Blank ballots | 7,285 | 1.14 | –0.54 | | |
| Total | Total | 639,880 | | | 8 | ±0 |
| Valid votes | Valid votes | 639,880 | 98.99 | –0.04 | | |
| Invalid votes | Invalid votes | 6,552 | 1.01 | +0.04 | | |
| Votes cast / turnout | Votes cast / turnout | 646,432 | 68.08 | +1.49 | | |
| Abstentions | Abstentions | 303,039 | 31.92 | –1.49 | | |
| Registered voters | Registered voters | 949,471 | | | | |
| Sources |||||||
| Footnotes: $^1$ Amaiur results are compared to the combined totals of Basque Solidarity and Aralar in the 2008 election. |||||||

### 2008 general election

Summary of the 9 March 2008 Congress of Deputies election results in Biscay :
| Parties and alliances | Parties and alliances | Popular vote | Popular vote | Popular vote | Seats | Seats |
| Parties and alliances | Parties and alliances | Votes | % | ±pp | Total | +/− |
| | Socialist Party of the Basque Country–Basque Country Left (PSE–EE (PSOE)) | 233,371 | 36.99 | +10.23 | 4 | +1 |
| | Basque Nationalist Party (EAJ/PNV) | 196,242 | 31.10 | –6.19 | 3 | –1 |
| | People's Party (PP) | 116,110 | 18.40 | –0.34 | 1 | –1 |
| | United Left–Greens–Alternative (EB–B) | 27,471 | 4.35 | –4.23 | 0 | ±0 |
| | Basque Solidarity (EA) | 19,605 | 3.11 | –1.23 | 0 | ±0 |
| | Aralar (Aralar) | 9,740 | 1.54 | –0.31 | 0 | ±0 |
| | Union, Progress and Democracy (UPyD) | 5,997 | 0.95 | New | 0 | ±0 |
| | The Greens (B/LV) | 3,351 | 0.53 | New | 0 | ±0 |
| | Anti-Bullfighting Party Against Mistreatment of Animals (PACMA) | 2,343 | 0.37 | New | 0 | ±0 |
| | For a Fairer World (PUM+J) | 1,466 | 0.23 | New | 0 | ±0 |
| | Internationalist Socialist Workers' Party (POSI) | 998 | 0.16 | –0.08 | 0 | ±0 |
| | Communist Party of the Peoples of Spain–Basque Communists (PCPE–EK) | 799 | 0.13 | New | 0 | ±0 |
| | Engine and Sports Alternative (AMD) | 617 | 0.10 | New | 0 | ±0 |
| | Family and Life Party (PFyV) | 589 | 0.09 | New | 0 | ±0 |
| | Humanist Party (PH) | 435 | 0.07 | –0.20 | 0 | ±0 |
| | Citizens–Party of the Citizenry (C's) | 426 | 0.07 | New | 0 | ±0 |
| | Spanish Phalanx of the CNSO (FE–JONS) | 219 | 0.03 | +0.01 | 0 | ±0 |
| | National Democracy (DN) | 191 | 0.03 | –0.02 | 0 | ±0 |
| | Carlist Party of the Basque Country–Carlist Party (EKA–PC) | 166 | 0.03 | –0.01 | 0 | ±0 |
| | Spanish Alternative (AES) | 113 | 0.02 | New | 0 | ±0 |
| | National Alliance (AN) | 87 | 0.01 | New | 0 | ±0 |
| Blank ballots | Blank ballots | 10,581 | 1.68 | +0.42 | | |
| Total | Total | 630,917 | | | 8 | –1 |
| Valid votes | Valid votes | 630,917 | 99.03 | +5.25 | | |
| Invalid votes | Invalid votes | 6,177 | 0.97 | –5.25 | | |
| Votes cast / turnout | Votes cast / turnout | 637,094 | 66.59 | –9.24 | | |
| Abstentions | Abstentions | 319,615 | 33.41 | +9.24 | | |
| Registered voters | Registered voters | 956,709 | | | | |
| Sources |||||||

### 2004 general election

Summary of the 14 March 2004 Congress of Deputies election results in Biscay :
| Parties and alliances | Parties and alliances | Popular vote | Popular vote | Popular vote | Seats | Seats |
| Parties and alliances | Parties and alliances | Votes | % | ±pp | Total | +/− |
| | Basque Nationalist Party (EAJ/PNV) | 258,488 | 37.29 | +3.08 | 4 | ±0 |
| | Socialist Party of the Basque Country–Basque Country Left (PSE–EE (PSOE)) | 185,514 | 26.76 | +3.90 | 3 | +1 |
| | People's Party (PP) | 129,889 | 18.74 | –8.52 | 2 | –1 |
| | United Left (EB/IU) | 59,493 | 8.58 | +2.79 | 0 | ±0 |
| | Basque Solidarity (EA) | 30,096 | 4.34 | –0.74 | 0 | ±0 |
| | Aralar–Stand up (Aralar–Zutik) | 12,791 | 1.85 | New | 0 | ±0 |
| | Party of the Democratic Karma (PKD) | 2,300 | 0.33 | –0.09 | 0 | ±0 |
| | Humanist Party (PH) | 1,846 | 0.27 | +0.03 | 0 | ±0 |
| | Internationalist Socialist Workers' Party (POSI) | 1,682 | 0.24 | +0.14 | 0 | ±0 |
| | Democratic and Social Centre (CDS) | 789 | 0.11 | +0.06 | 0 | ±0 |
| | Republican Left (IR) | 407 | 0.06 | New | 0 | ±0 |
| | National Democracy (DN) | 348 | 0.05 | New | 0 | ±0 |
| | Republican Social Movement (MSR) | 264 | 0.04 | New | 0 | ±0 |
| | Carlist Party of the Basque Country–Carlist Party (EKA–PC) | 243 | 0.04 | New | 0 | ±0 |
| | The Phalanx (FE) | 147 | 0.02 | –0.02 | 0 | ±0 |
| | Spanish Phalanx of the CNSO (FE–JONS)$^1$ | 134 | 0.02 | –0.01 | 0 | ±0 |
| Blank ballots | Blank ballots | 8,754 | 1.26 | –1.44 | | |
| Total | Total | 693,185 | | | 9 | ±0 |
| Valid votes | Valid votes | 693,185 | 93.78 | –5.13 | | |
| Invalid votes | Invalid votes | 45,979 | 6.22 | +5.13 | | |
| Votes cast / turnout | Votes cast / turnout | 739,164 | 75.83 | +8.84 | | |
| Abstentions | Abstentions | 235,578 | 24.17 | –8.84 | | |
| Registered voters | Registered voters | 974,742 | | | | |
| Sources |||||||
| Footnotes: $^1$ Spanish Phalanx of the CNSO results are compared to Independent Spanish Phalanx–Phalanx 2000 totals in the 2000 election. |||||||

### 2000 general election

Summary of the 12 March 2000 Congress of Deputies election results in Biscay :
| Parties and alliances | Parties and alliances | Popular vote | Popular vote | Popular vote | Seats | Seats |
| Parties and alliances | Parties and alliances | Votes | % | ±pp | Total | +/− |
| | Basque Nationalist Party (EAJ/PNV) | 222,479 | 34.21 | +5.01 | 4 | +1 |
| | People's Party (PP) | 177,272 | 27.26 | +8.82 | 3 | +1 |
| | Socialist Party of the Basque Country–Basque Country Left (PSE–EE (PSOE)) | 148,670 | 22.86 | –0.93 | 2 | ±0 |
| | United Left (EB/IU) | 37,677 | 5.79 | –3.93 | 0 | –1 |
| | Basque Solidarity (EA) | 33,047 | 5.08 | –0.10 | 0 | ±0 |
| | The Greens (B/LV) | 5,469 | 0.84 | +0.40 | 0 | ±0 |
| | Party of the Democratic Karma (PKD) | 2,759 | 0.42 | New | 0 | ±0 |
| | Humanist Party (PH) | 1,579 | 0.24 | +0.18 | 0 | ±0 |
| | Natural Law Party (PLN) | 1,025 | 0.16 | New | 0 | ±0 |
| | Internationalist Socialist Workers' Party (POSI) | 662 | 0.10 | New | 0 | ±0 |
| | Communist Party of the Peoples of Spain (PCPE) | 534 | 0.08 | New | 0 | ±0 |
| | Democratic and Social Centre–Centrist Union (CDS–UC) | 348 | 0.05 | –0.01 | 0 | ±0 |
| | Republican Action (AR) | 281 | 0.04 | New | 0 | ±0 |
| | Spain 2000 Platform (ES2000) | 246 | 0.04 | New | 0 | ±0 |
| | The Phalanx (FE) | 243 | 0.04 | New | 0 | ±0 |
| | Carlist Party (EKA) | 182 | 0.03 | New | 0 | ±0 |
| | Independent Spanish Phalanx–Phalanx 2000 (FEI–FE 2000) | 179 | 0.03 | +0.01 | 0 | ±0 |
| | Internationalist Struggle (LI (LIT–CI)) | 151 | 0.02 | New | 0 | ±0 |
| | Basque Citizens (EH)$^1$ | 0 | 0.00 | –9.94 | 0 | –1 |
| Blank ballots | Blank ballots | 17,584 | 2.70 | +1.40 | | |
| Total | Total | 650,387 | | | 9 | ±0 |
| Valid votes | Valid votes | 650,387 | 98.91 | –0.41 | | |
| Invalid votes | Invalid votes | 7,138 | 1.09 | +0.41 | | |
| Votes cast / turnout | Votes cast / turnout | 657,525 | 66.99 | –5.50 | | |
| Abstentions | Abstentions | 324,046 | 33.01 | +5.50 | | |
| Registered voters | Registered voters | 981,571 | | | | |
| Sources |||||||
| Footnotes: $^1$ Basque Citizens results are compared to Popular Unity totals in the 1996 election. EH called for election boycott and urged its supporters to abstain. |||||||

### 1996 general election

Summary of the 3 March 1996 Congress of Deputies election results in Biscay :
| Parties and alliances | Parties and alliances | Popular vote | Popular vote | Popular vote | Seats | Seats |
| Parties and alliances | Parties and alliances | Votes | % | ±pp | Total | +/− |
| | Basque Nationalist Party (EAJ/PNV) | 204,056 | 29.20 | –0.34 | 3 | ±0 |
| | Socialist Party of the Basque Country–Basque Country Left (PSE–EE (PSOE)) | 166,293 | 23.79 | –1.08 | 2 | –1 |
| | People's Party (PP) | 128,904 | 18.44 | +3.15 | 2 | ±0 |
| | Popular Unity (HB) | 69,472 | 9.94 | –2.58 | 1 | ±0 |
| | United Left (IU/EB) | 67,954 | 9.72 | +2.67 | 1 | +1 |
| | Basque Solidarity (EA) | 36,234 | 5.18 | –1.13 | 0 | ±0 |
| | Basque Citizen Initiative (ICV–Gorordo) | 11,833 | 1.69 | New | 0 | ±0 |
| | European Greens–Basque Country Greens (VE–EHB) | 774 | 0.44 | –0.57 | 0 | ±0 |
| | Workers' Revolutionary Party (PRT)$^1$ | 560 | 0.08 | –0.38 | 0 | ±0 |
| | Centrist Union (UC) | 430 | 0.06 | –0.73 | 0 | ±0 |
| | Humanist Party (PH) | 394 | 0.06 | +0.01 | 0 | ±0 |
| | Republican Coalition (CR)$^2$ | 331 | 0.05 | +0.01 | 0 | ±0 |
| | Authentic Spanish Phalanx (FEA) | 139 | 0.02 | New | 0 | ±0 |
| | Independent Spanish Phalanx (FEI) | 138 | 0.02 | New | 0 | ±0 |
| | Revolutionary Workers' Party (POR) | 0 | 0.00 | –0.06 | 0 | ±0 |
| Blank ballots | Blank ballots | 9,063 | 1.30 | +0.09 | | |
| Total | Total | 698,859 | | | 9 | ±0 |
| Valid votes | Valid votes | 698,859 | 99.32 | +0.14 | | |
| Invalid votes | Invalid votes | 4,770 | 0.68 | –0.14 | | |
| Votes cast / turnout | Votes cast / turnout | 703,629 | 72.49 | +1.41 | | |
| Abstentions | Abstentions | 266,963 | 27.51 | –1.41 | | |
| Registered voters | Registered voters | 970,592 | | | | |
| Sources |||||||
| Footnotes: $^1$ Workers' Revolutionary Party results are compared to Workers' Socialist Party totals in the 1993 election.$^2$ Republican Coalition results are compared to Coalition for a New Socialist Party totals in the 1993 election. |||||||

### 1993 general election

Summary of the 6 June 1993 Congress of Deputies election results in Biscay :
| Parties and alliances | Parties and alliances | Popular vote | Popular vote | Popular vote | Seats | Seats |
| Parties and alliances | Parties and alliances | Votes | % | ±pp | Total | +/− |
| | Basque Nationalist Party (EAJ/PNV) | 197,392 | 29.54 | +1.63 | 3 | ±0 |
| | Socialist Party of the Basque Country–Basque Country Left (PSE–EE (PSOE))$^1$ | 166,172 | 24.87 | –3.81 | 3 | ±0 |
| | People's Party (PP) | 102,172 | 15.29 | +5.59 | 2 | +1 |
| | Popular Unity (HB) | 83,644 | 12.52 | –2.53 | 1 | –1 |
| | United Left (IU/EB) | 47,091 | 7.05 | +3.44 | 0 | ±0 |
| | Basque Solidarity–Basque Left (EA–EuE) | 42,175 | 6.31 | –1.56 | 0 | –1 |
| | The Greens (Berdeak/LV) | 6,769 | 1.01 | New | 0 | ±0 |
| | Democratic and Social Centre (CDS) | 5,285 | 0.79 | –2.65 | 0 | ±0 |
| | The Ecologists (LE) | 3,215 | 0.48 | –0.59 | 0 | ±0 |
| | Workers' Socialist Party (PST) | 3,053 | 0.46 | +0.12 | 0 | ±0 |
| | Ruiz-Mateos Group–European Democratic Alliance (ARM–ADE) | 1,359 | 0.20 | –0.56 | 0 | ±0 |
| | Referendum Tolerant Independent Political Party (PITRCG) | 408 | 0.06 | New | 0 | ±0 |
| | Revolutionary Workers' Party (POR) | 405 | 0.06 | –0.02 | 0 | ±0 |
| | Natural Law Party (PLN) | 387 | 0.06 | New | 0 | ±0 |
| | Humanist Party (PH) | 353 | 0.05 | –0.03 | 0 | ±0 |
| | Coalition for a New Socialist Party (CNPS)$^2$ | 251 | 0.04 | –0.02 | 0 | ±0 |
| | Communist Unification of Spain (UCE) | 0 | 0.00 | New | 0 | ±0 |
| Blank ballots | Blank ballots | 8,060 | 1.21 | +0.53 | | |
| Total | Total | 668,191 | | | 9 | –1 |
| Valid votes | Valid votes | 668,191 | 99.18 | +0.15 | | |
| Invalid votes | Invalid votes | 5,495 | 0.82 | –0.15 | | |
| Votes cast / turnout | Votes cast / turnout | 673,686 | 71.08 | +3.79 | | |
| Abstentions | Abstentions | 274,085 | 28.92 | –3.79 | | |
| Registered voters | Registered voters | 947,771 | | | | |
| Sources |||||||
| Footnotes: $^1$ Socialist Party of the Basque Country–Basque Country Left results are compared to the combined totals of Socialist Party of the Basque Country and Basque Country Left in the 1989 election.$^2$ Coalition for a New Socialist Party results are compared to Alliance for the Republic totals in the 1989 election. |||||||

### 1989 general election

Summary of the 29 October 1989 Congress of Deputies election results in Biscay :
| Parties and alliances | Parties and alliances | Popular vote | Popular vote | Popular vote | Seats | Seats |
| Parties and alliances | Parties and alliances | Votes | % | ±pp | Total | +/− |
| | Basque Nationalist Party (EAJ/PNV) | 171,582 | 27.91 | –1.40 | 3 | ±0 |
| | Socialist Party of the Basque Country (PSE–PSOE) | 127,744 | 20.78 | –5.78 | 2 | –1 |
| | Popular Unity (HB) | 92,493 | 15.05 | –0.86 | 2 | ±0 |
| | People's Party (PP)$^1$ | 59,632 | 9.70 | –0.97 | 1 | ±0 |
| | Basque Country Left (EE) | 48,559 | 7.90 | –0.46 | 1 | ±0 |
| | Basque Solidarity (EA) | 48,355 | 7.87 | New | 1 | +1 |
| | United Left (IU/EB) | 22,169 | 3.61 | +2.03 | 0 | ±0 |
| | Democratic and Social Centre (CDS) | 21,144 | 3.44 | –1.51 | 0 | ±0 |
| | The Ecologist Greens (LVE) | 6,589 | 1.07 | New | 0 | ±0 |
| | Ruiz-Mateos Group (Ruiz-Mateos) | 4,682 | 0.76 | New | 0 | ±0 |
| | Workers' Party of the Basque Country–Basque Country Workers (PTE–EL)$^2$ | 3,125 | 0.51 | –0.61 | 0 | ±0 |
| | Workers' Socialist Party (PST) | 2,099 | 0.34 | –0.10 | 0 | ±0 |
| | Communist Party of the Peoples of Spain (PCPE) | 546 | 0.09 | New | 0 | ±0 |
| | Humanist Party (PH) | 521 | 0.08 | New | 0 | ±0 |
| | Revolutionary Workers' Party of Spain (PORE) | 510 | 0.08 | New | 0 | ±0 |
| | Spanish Phalanx of the CNSO (FE–JONS) | 400 | 0.07 | –0.05 | 0 | ±0 |
| | Alliance for the Republic (AxR)$^3$ | 398 | 0.06 | –0.10 | 0 | ±0 |
| | Communist Party of Spain (Marxist–Leninist) (PCE (m–l))$^4$ | 0 | 0.00 | –0.12 | 0 | ±0 |
| | Revolutionary Communist League–Communist Movement (LKI–EMK)$^5$ | 0 | 0.00 | ±0.00 | 0 | ±0 |
| Blank ballots | Blank ballots | 4,176 | 0.68 | +0.20 | | |
| Total | Total | 614,724 | | | 10 | ±0 |
| Valid votes | Valid votes | 614,724 | 99.03 | +1.04 | | |
| Invalid votes | Invalid votes | 6,044 | 0.97 | –1.04 | | |
| Votes cast / turnout | Votes cast / turnout | 620,768 | 67.29 | –1.03 | | |
| Abstentions | Abstentions | 301,825 | 32.71 | +1.03 | | |
| Registered voters | Registered voters | 922,593 | | | | |
| Sources |||||||
| Footnotes: $^1$ People's Party results are compared to People's Coalition totals in the 1986 election.$^2$ Workers' Party of the Basque Country–Basque Country Workers results are compared to Communist Party of the Basque Country totals in the 1986 election.$^3$ Alliance for the Republic results are compared to Internationalist Socialist Workers' Party totals in the 1986 election.$^4$ Communist Party of Spain (Marxist–Leninist) results are compared to Republican Popular Unity totals in the 1986 election.$^5$ Revolutionary Communist League–Communist Movement results are compared to the combined totals of Communist Movement of the Basque Country and Revolutionary Communist League in the 1986 election. |||||||

### 1986 general election

Summary of the 22 June 1986 Congress of Deputies election results in Biscay :
| Parties and alliances | Parties and alliances | Popular vote | Popular vote | Popular vote | Seats | Seats |
| Parties and alliances | Parties and alliances | Votes | % | ±pp | Total | +/− |
| | Basque Nationalist Party (EAJ/PNV) | 179,130 | 29.31 | –4.07 | 3 | –1 |
| | Socialist Party of the Basque Country (PSE–PSOE) | 162,323 | 26.56 | –3.08 | 3 | –1 |
| | Popular Unity (HB) | 97,252 | 15.91 | +2.80 | 2 | +1 |
| | People's Coalition (AP–PDP–PL)$^1$ | 65,212 | 10.67 | –1.35 | 1 | ±0 |
| | Basque Country Left (EE) | 51,090 | 8.36 | +1.80 | 1 | +1 |
| | Democratic and Social Centre (CDS) | 30,286 | 4.95 | +3.47 | 0 | ±0 |
| | United Left (IU) | 9,638 | 1.58 | New | 0 | ±0 |
| | Communist Party of the Basque Country (PCE/EPK) | 6,863 | 1.12 | –1.07 | 0 | ±0 |
| | Workers' Socialist Party (PST) | 2,659 | 0.44 | –0.13 | 0 | ±0 |
| | Communist Unification of Spain (UCE) | 1,397 | 0.23 | +0.05 | 0 | ±0 |
| | Internationalist Socialist Workers' Party (POSI) | 981 | 0.16 | New | 0 | ±0 |
| | Spanish Phalanx of the CNSO (FE–JONS) | 751 | 0.12 | New | 0 | ±0 |
| | Republican Popular Unity (UPR)$^2$ | 704 | 0.12 | +0.05 | 0 | ±0 |
| | Communist Movement of the Basque Country (EMK) | 0 | 0.00 | ±0.00 | 0 | ±0 |
| | Revolutionary Communist League (LKI) | 0 | 0.00 | ±0.00 | 0 | ±0 |
| | Party of the Communists of Catalonia (PCC) | 0 | 0.00 | New | 0 | ±0 |
| Blank ballots | Blank ballots | 2,935 | 0.48 | –0.02 | | |
| Total | Total | 611,221 | | | 10 | ±0 |
| Valid votes | Valid votes | 611,221 | 97.99 | +0.16 | | |
| Invalid votes | Invalid votes | 12,549 | 2.01 | –0.16 | | |
| Votes cast / turnout | Votes cast / turnout | 623,770 | 68.32 | –11.20 | | |
| Abstentions | Abstentions | 289,194 | 31.68 | +11.20 | | |
| Registered voters | Registered voters | 912,964 | | | | |
| Sources |||||||
| Footnotes: $^1$ People's Coalition results are compared to AP–PDP–PDL–UCD totals in the 1982 election.$^2$ Republican Popular Unity results are compared to Communist Party of Spain (Marxist–Leninist) totals in the 1982 election. |||||||

### 1982 general election

Summary of the 28 October 1982 Congress of Deputies election results in Biscay :
| Parties and alliances | Parties and alliances | Popular vote | Popular vote | Popular vote | Seats | Seats |
| Parties and alliances | Parties and alliances | Votes | % | ±pp | Total | +/− |
| | Basque Nationalist Party (EAJ/PNV) | 221,801 | 33.38 | +4.20 | 4 | ±0 |
| | Socialist Party of the Basque Country (PSE–PSOE) | 196,974 | 29.64 | +10.58 | 4 | +2 |
| | Popular Unity (HB) | 87,100 | 13.11 | –1.40 | 1 | –1 |
| | Democratic Coalition (AP–PDP–PDL–UCD)$^1$ | 79,866 | 12.02 | –8.20 | 1 | –1 |
| | Basque Country Left–Left for Socialism (EE) | 43,591 | 6.56 | +0.71 | 0 | ±0 |
| | Communist Party of the Basque Country (PCE/EPK) | 14,537 | 2.19 | –3.58 | 0 | ±0 |
| | Democratic and Social Centre (CDS) | 9,815 | 1.48 | New | 0 | ±0 |
| | Workers' Socialist Party (PST) | 3,815 | 0.57 | New | 0 | ±0 |
| | New Force (FN)$^2$ | 1,289 | 0.19 | –1.17 | 0 | ±0 |
| | Communist Unification of Spain (UCE) | 1,225 | 0.18 | New | 0 | ±0 |
| | Communist Unity Candidacy (CUC) | 761 | 0.11 | New | 0 | ±0 |
| | Communist Party of Spain (Marxist–Leninist) (PCE (m–l)) | 478 | 0.07 | New | 0 | ±0 |
| | Revolutionary Communist League (LKI) | 0 | 0.00 | –0.55 | 0 | ±0 |
| | Socialist Party (PS)$^3$ | 0 | 0.00 | –0.75 | 0 | ±0 |
| | Communist League–Internationalist Socialist Workers' Coalition (LC (COSI)) | 0 | 0.00 | New | 0 | ±0 |
| | Communist Movement of the Basque Country (EMK) | 0 | 0.00 | –1.32 | 0 | ±0 |
| Blank ballots | Blank ballots | 3,318 | 0.50 | +0.30 | | |
| Total | Total | 664,570 | | | 10 | ±0 |
| Valid votes | Valid votes | 664,570 | 97.83 | +0.04 | | |
| Invalid votes | Invalid votes | 14,728 | 2.17 | –0.04 | | |
| Votes cast / turnout | Votes cast / turnout | 679,298 | 79.52 | +14.19 | | |
| Abstentions | Abstentions | 174,906 | 20.48 | –14.19 | | |
| Registered voters | Registered voters | 854,204 | | | | |
| Sources |||||||
| Footnotes: $^1$ AP–PDP–PDL–UCD results are compared to the combined totals of the Foral Union of the Basque Country and Union of the Democratic Centre in the 1979 election.$^2$ New Force results are compared to National Union totals in the 1979 election.$^3$ Socialist Party results are compared to Spanish Socialist Workers' Party (historical) totals in the 1979 election. |||||||

### 1979 general election

Summary of the 1 March 1979 Congress of Deputies election results in Biscay :
| Parties and alliances | Parties and alliances | Popular vote | Popular vote | Popular vote | Seats | Seats |
| Parties and alliances | Parties and alliances | Votes | % | ±pp | Total | +/− |
| | Basque Nationalist Party (EAJ/PNV) | 161,480 | 29.18 | –1.74 | 4 | ±0 |
| | Socialist Party of the Basque Country (PSE–PSOE)$^1$ | 105,481 | 19.06 | –8.38 | 2 | –1 |
| | Union of the Democratic Centre (UCD) | 88,431 | 15.98 | –0.43 | 2 | ±0 |
| | Popular Unity (HB)$^2$ | 80,280 | 14.51 | +10.97 | 2 | +2 |
| | Basque Country Left (EE) | 32,363 | 5.85 | +0.42 | 0 | ±0 |
| | Communist Party of the Basque Country (PCE/EPK) | 31,942 | 5.77 | +0.38 | 0 | ±0 |
| | Foral Union of the Basque Country (UFPV)$^3$ | 23,484 | 4.24 | –2.40 | 0 | –1 |
| | National Union (UN) | 7,521 | 1.36 | New | 0 | ±0 |
| | Communist Movement–Organization of Communist Left (MC–OIC) | 7,292 | 1.32 | New | 0 | ±0 |
| | Spanish Socialist Workers' Party (historical) (PSOEh)$^4$ | 4,131 | 0.75 | –0.37 | 0 | ±0 |
| | Revolutionary Communist League (LCR)$^5$ | 3,039 | 0.55 | –0.26 | 0 | ±0 |
| | Workers' Revolutionary Organization (ORT)$^6$ | 2,932 | 0.53 | +0.02 | 0 | ±0 |
| | Carlist Party (PC) | 1,380 | 0.25 | New | 0 | ±0 |
| | Republican Left of the Basque Country (IR–E) | 1,229 | 0.22 | New | 0 | ±0 |
| | Spanish Phalanx of the CNSO (Authentic) (FE–JONS(A)) | 795 | 0.14 | New | 0 | ±0 |
| | Proverist Party (PPr) | 500 | 0.09 | New | 0 | ±0 |
| | Union for the Freedom of Speech (ULE) | 0 | 0.00 | New | 0 | ±0 |
| Blank ballots | Blank ballots | 1,127 | 0.20 | –0.01 | | |
| Total | Total | 553,407 | | | 10 | ±0 |
| Valid votes | Valid votes | 553,407 | 97.79 | +0.64 | | |
| Invalid votes | Invalid votes | 12,478 | 2.21 | –0.64 | | |
| Votes cast / turnout | Votes cast / turnout | 565,885 | 65.33 | –11.05 | | |
| Abstentions | Abstentions | 300,300 | 34.67 | +11.05 | | |
| Registered voters | Registered voters | 866,185 | | | | |
| Sources |||||||
| Footnotes: $^1$ Socialist Party of the Basque Country results are compared to the combined totals of Socialist Party of the Basque Country and People's Socialist Party–Socialist Unity in the 1977 election.$^2$ Popular Unity results are compared to the combined totals of the Basque Socialist Party and Basque Nationalist Action in the 1977 election.$^3$ Foral Union of the Basque Country results are compared to People's Alliance totals in the 1977 election.$^4$ Spanish Socialist Workers' Party (historical) results are compared to Democratic Socialist Alliance totals in the 1977 election.$^5$ Revolutionary Communist League results are compared to Front for Workers' Unity totals in the 1977 election.$^6$ Workers' Revolutionary Organization results are compared to Workers' Electoral Group totals in the 1977 election. |||||||

### 1977 general election

Summary of the 15 June 1977 Congress of Deputies election results in Biscay :
| Parties and alliances | Parties and alliances | Popular vote | Popular vote | Popular vote | Seats | Seats |
| Parties and alliances | Parties and alliances | Votes | % | ±pp | Total | +/− |
| | Basque Nationalist Party (EAJ/PNV) | 171,991 | 30.92 | n/a | 4 | n/a |
| | Socialist Party of the Basque Country (PSE–PSOE) | 140,643 | 25.28 | n/a | 3 | n/a |
| | Union of the Democratic Centre (UCD) | 91,262 | 16.41 | n/a | 2 | n/a |
| | People's Alliance (AP) | 36,934 | 6.64 | n/a | 1 | n/a |
| | Basque Country Left (EE) | 30,209 | 5.43 | n/a | 0 | n/a |
| | Communist Party of the Basque Country (PCE/EPK) | 29,968 | 5.39 | n/a | 0 | n/a |
| | Basque Socialist Party (ESB/PSV) | 15,079 | 2.71 | n/a | 0 | n/a |
| | People's Socialist Party–Socialist Unity (PSP–US) | 12,038 | 2.16 | n/a | 0 | n/a |
| | Democratic Socialist Alliance (ASDCI) | 6,224 | 1.12 | n/a | 0 | n/a |
| | Basque Christian Democracy (DCV) | 6,034 | 1.08 | n/a | 0 | n/a |
| | Basque Nationalist Action (EAE/ANV) | 4,617 | 0.83 | n/a | 0 | n/a |
| | Front for Workers' Unity (FUT) | 4,478 | 0.81 | n/a | 0 | n/a |
| | Workers' Electoral Group (AET) | 2,825 | 0.51 | n/a | 0 | n/a |
| | Democratic Left Front (FDI) | 2,767 | 0.50 | n/a | 0 | n/a |
| Blank ballots | Blank ballots | 1,166 | 0.21 | n/a | | |
| Total | Total | 556,235 | | | 10 | n/a |
| Valid votes | Valid votes | 556,235 | 97.15 | n/a | | |
| Invalid votes | Invalid votes | 16,313 | 2.85 | n/a | | |
| Votes cast / turnout | Votes cast / turnout | 572,548 | 76.38 | n/a | | |
| Abstentions | Abstentions | 177,024 | 23.62 | n/a | | |
| Registered voters | Registered voters | 749,572 | | | | |
| Sources |||||||