1991 Madrid City Council election
The 1991 Madrid City Council election, also the 1991 Madrid municipal election, was held on Sunday, 26 May 1991, to elect the 4th City Council of the municipality of Madrid. All 57 seats in the City Council were up for election. The election was held simultaneously with regional elections in thirteen autonomous communities and local elections all throughout Spain.
The People's Party, People's Alliance new electoral brand, went on to win a City Council election in Madrid for the first time with an absolute majority of seats. The Spanish Socialist Workers' Party continued its decline in the city and lost 3 seats and around 150,000 votes, while United Left recovered from its 1987 debacle and, for the first time since 1979, increased in seats and votes. The ruling Democratic and Social Centre, whose local leader Agustín Rodríguez Sahagún had announced his intention not to run for re-election, all but disappeared from the Council after failing to meet the required 5% threshold.
As a result of the election, José María Álvarez del Manzano was elected Mayor unopposed, a post he would retain until 2003, becoming the longest-serving democratically elected Mayor of Madrid.
Electoral system
The City Council of Madrid was the top-tier administrative and governing body of the municipality of Madrid, composed of the mayor, the government council and the elected plenary assembly. Elections to the local councils in Spain were fixed for the fourth Sunday of May every four years.Voting for the local assembly was on the basis of universal suffrage, which comprised all nationals over eighteen, registered in the municipality of Madrid and in full enjoyment of their political rights, as well as resident non-nationals whose country of origin allowed Spanish nationals to vote in their own elections by virtue of a treaty. Local councillors were elected using the D'Hondt method and a closed list proportional representation, with a threshold of five percent of valid votes—which included blank ballots—being applied in each local council. Parties not reaching the threshold were not taken into consideration for seat distribution. Councillors were allocated to municipal councils based on the following scale:
| Population | Councillors |
| <250 | 5 |
| 251–1,000 | 7 |
| 1,001–2,000 | 9 |
| 2,001–5,000 | 11 |
| 5,001–10,000 | 13 |
| 10,001–20,000 | 17 |
| 20,001–50,000 | 21 |
| 50,001–100,000 | 25 |
| >100,001 | +1 per each 100,000 inhabitants or fraction +1 if total is an even number |
The mayor was indirectly elected by the plenary assembly. A legal clause required that mayoral candidates earned the vote of an absolute majority of councillors, or else the candidate of the most-voted party in the assembly was to be automatically appointed to the post. In the event of a tie, a toss-up would determine the appointee.
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 a determined amount of the electors registered in the municipality for which they were seeking election, disallowing electors from signing for more than one list of candidates. For the case of Madrid, as its population was over 1,000,001, at least 8,000 signatures were required.