Who actually runs Spain? The King? The prime minister? Parliament? If you read Spanish news for long enough, you'll see all three described as making decisions, plus a Constitutional Court that can overturn laws and seventeen regional governments with their own parliaments.
This guide untangles it: who does what, who gets elected and how often, and how the pieces keep each other in check.
It all starts with the 1978 Constitution
Spain's current system rests on one document: the Constitution approved by referendum on 6 December 1978, three years after Franco's death and after almost four decades of dictatorship. Article 1 sets out three ideas that everything else follows from:
- Rule of law:Spain is a social and democratic state under the rule of law (Estado social y democrático de Derecho).
- Popular sovereignty:sovereignty belongs to the Spanish people, so power comes from voters, not from the crown.
- Parliamentary monarchy:the form of government (Monarquía parlamentaria): a king as head of state, a government chosen through parliament.
That last word, parliamentary, is the key to the rest of this article. Spain has a king, but the people who govern are chosen through parliament.
Three branches of power, and a King above them
Like most democracies, Spain splits power three ways:
- Legislative:the Cortes Generales (parliament) pass laws and the budget.
- Executive:the Government (Gobierno) runs the country.
- Judicial:judges and courts (Jueces y Tribunales) administer justice.
The King sits above all three as head of state and arbiter — but he is not a branch of power himself.
The King reigns, but does not rule
Spain's head of state is King Felipe VI, on the throne since 2014. Nobody votes for him: the crown is hereditary.
On paper his list of duties looks powerful. He signs and promulgates laws, convenes and dissolves parliament, calls elections, nominates the candidate for prime minister, is supreme commander of the armed forces and represents Spain abroad.
The catch is a mechanism called el refrendo (countersignature). Almost every act the King signs must be countersigned by the prime minister or a minister, and they — not the King — bear political responsibility for it. In practice, he formalises decisions others have already taken.
The King is the symbol of the state and its formal arbiter. Real political decisions are made by the Government and parliament, which answer to voters.
Parliament: the Cortes Generales
Spain's parliament, the Cortes Generales, has two chambers: the Congress of Deputies and the Senate.
Congress seats 350 elected every 4 years
Absolute majority 176 the number to remember
Senate seats ≈266 209 elected + ≈57 regional
The Congress of Deputies (Congreso de los Diputados) has 350 seats, elected every four years by proportional representation, province by province. The number to remember is 176: an absolute majority. It comes up again and again — to elect a prime minister in the first vote, and to remove one.
The Senate is a mix: 209 senators are elected directly (generally four per province, and from the 2026 election one for Formentera), and around 57 more are appointed by the regional parliaments, so the exact size shifts slightly with population.
Both chambers pass laws, but Congress always has the final word.
Congress vs Senate: two chambers, unequal power
Why have two chambers at all? Because they do very different jobs.
- How you vote:Congress — closed party lists. Senate — you tick named candidates (up to three per province).
- Choosing the PM:Congress only, through the investiture vote.
- Bringing the government down:Congress only, through a motion of censure.
- Laws:the Senate can amend or veto a bill, but Congress can override it.
- The Senate's one big power:approving Article 155, which lets the central state step in when a region breaks the law (used once, in Catalonia in 2017).
Both chambers are elected on the same day, for the same four years — but only Congress decides who governs.
- 1Congressdebates and passes the bill
- 2Senateapproves it, amends it or vetoes it
- 3Congress againhas the final word and can override the Senate
- 4The Kingsigns and promulgates the law
How the prime minister is chosen
This is the part that surprises most newcomers: Spaniards do not vote for their prime minister directly. They vote for parties, and the prime minister (officially Presidente del Gobierno) is whoever can win a vote in Congress.
The process runs in five steps:
- 1. Election:citizens vote for party lists (elecciones generales).
- 2. 350 seats:seats in Congress are shared out among parties.
- 3. The King:he consults the leader of every party with seats (ronda de consultas) and nominates a candidate.
- 4. Investiture:the candidate needs 176 votes in the first vote. If they fail, 48 hours later a simple majority — more yes than no — is enough.
- 5. Prime minister:the King formally appoints the winner, who then picks the ministers.
If no candidate wins within two months of the first investiture vote, parliament is automatically dissolved and a new election is called. That's what happened in 2016 and again in 2019.
How steps 1 and 2 actually work, from the 52 electoral districts to the d'Hondt formula and why a blank vote can knock a small party out, is explained step by step in our guide to how Spain votes.
- The King nominates a candidateafter meeting every party leader with seats, the ronda de consultas
- First vote in Congressthe candidate needs 176 yes votes, an absolute majority YesThe King appoints the prime minister
- Second vote, 48 hours laternow more yes than no is enough; abstentions help YesThe King appoints the prime minister
- Still no prime minister after two months?counted from the first vote: parliament is dissolved and Spain votes again, as in 2016 and 2019
When Spanish news talks about "pactos" or "negociaciones" after an election, this is why: with no party holding 176 seats on its own, the candidate has to collect enough yes votes (or abstentions) from other parties to pass the investiture.
The Government, kept in check
The Government is the Council of Ministers (Consejo de Ministros): the prime minister, any deputy prime ministers and the ministers. The PM appoints and dismisses ministers freely. The Government directs domestic and foreign policy, defence and public administration, drafts the budget, and can pass emergency decree-laws — which Congress must approve within 30 days or they lapse.
Congress holds it to account in three ways:
- Motion of censure:the moción de censura must be constructive — 176 votes and a named replacement PM. That is exactly how the government changed in 2018.
- Confidence vote:in a cuestión de confianza, the PM asks Congress to reaffirm its support.
- Control sessions:every week, in the sesiones de control, ministers answer MPs' questions in the chamber.
And it works both ways: the prime minister can ask the King to dissolve parliament early and call a snap election.
The courts: judges answer only to the law
The core principle of the judiciary is simple: judges are bound only by the law — not by the Government and not by parliament.
Ordinary courts form a pyramid. Most cases start in the courts of first instance at the bottom, go up through the Provincial Courts (Audiencias Provinciales) and the National High Court and Regional High Courts (Audiencia Nacional, TSJ), with the Supreme Court (Tribunal Supremo) at the top.
The judiciary is run by the General Council of the Judiciary (CGPJ): 20 members on five-year terms, 10 elected by Congress and 10 by the Senate, each by a three-fifths majority. It appoints and promotes judges and oversees discipline. The Attorney General (Fiscal General del Estado) is proposed by the Government and appointed by the King after hearing the CGPJ.
- Supreme CourtTribunal Supremo
- National High Court and Regional High CourtsAudiencia Nacional, TSJ
- Provincial CourtsAudiencias Provinciales
- Courts of first instanceTribunales de Instancia
Most cases start at the bottom tier, and appeals go up.
The Constitutional Court
Separate from the ordinary courts stands the Constitutional Court (Tribunal Constitucional), the guardian of the Constitution.
It has 12 judges: four chosen by Congress, four by the Senate, two by the Government and two by the CGPJ. They serve nine-year terms, and a third of the court is renewed every three years, so it never flips all at once with a change of political majority. The King formally appoints them.
Its three jobs:
- Reviewing whether laws comply with the Constitution — and striking them down if they don't.
- Protecting citizens' fundamental rights on appeal (recurso de amparo).
- Settling disputes between the central state and the regions.
Who elects and controls whom
Put it all together and you get a web where every institution is chosen or checked by another:
- Citizenselect the Cortes every four years — but not the prime minister directly.
- The Cortesinvest the Government, scrutinise it and can censure it.
- The Governmentcan trigger an early dissolution of parliament (via the King).
- Parliamentelects all 20 members of the CGPJ and 8 of the 12 constitutional judges.
- The Constitutional Courtcan strike down any law parliament passes.
Nobody has the last word on everything. That is the whole point of the design.
Power is split vertically too
Spain is a "State of Autonomies". Beyond Madrid, power is shared out among:
Autonomous communities 17 each with its own parliament
Autonomous cities 2 Ceuta and Melilla
Municipalities ≈8,100 plus 50 provinces
And the same pattern repeats at every level:
- Country:citizens elect Congress, which picks the prime minister. It handles defence, foreign policy and pensions.
- Region:citizens elect a regional parliament, which picks the regional president. It handles healthcare, education and, in some regions, policing.
- Town:citizens elect councillors, who choose the mayor. It handles streets, transport, waste and permits.
That is why your doctor's appointment depends on your region's health service, while your empadronamiento is done at the town hall.
How often Spaniards vote
- General elections:at least every four years, and sometimes early — like the snap election called for 29 November 2026. See how Spain votes for how those votes become seats.
- Regional elections:every four years; dates vary by region.
- Municipal elections:every four years, in May, on the same day across Spain.
- European elections:every five years, for 61 MEPs.
Some key posts are not chosen by voters at all: the King (for life, hereditary), the CGPJ (five years, elected by the Cortes), the Constitutional Court (nine years, a third every three years) and the Ombudsman (Defensor del Pueblo, five years, elected by the Cortes).
The big picture
Power in Spain is shared so it can't pile up in one place. Parliament makes the laws, the Government runs the country, and the courts apply the law. The King is the symbol and the arbiter, and the Constitution stands above them all.
Once you know that the prime minister needs Congress, that Congress needs 176 votes to change anything big, and that the regions run most day-to-day services, Spanish political news becomes a lot easier to follow. If you'd like that news in five minutes a day, in English, Spain Daily sends it every morning for free.