The position was left nominally vacant after Mariano Rajoy's government was ousted in a motion of no confidence on 2 June 2018, until the election of Pablo Casado as new PP leader.

From 23 February 2022, the position was again left vacant following the ousting of Casado by most of the leading members of his party, led by Galician and Madrilenian presidents Alberto Núñez Feijóo and Isabel Díaz Ayuso.

[3] Such an agreement, further expanded on 8 February 1983, established a series of conditions for the role and awarded some prerogatives for the officeholder: The Leader of the Opposition is entitled a special office in the Congress of Deputies if he or she is a member of the chamber.

[13] The first recognized Leader of the Opposition was Manuel Fraga,[14] who in February 1983 was granted such a formal status by the Congress of Deputies Bureau,[15][16] despite the rejection of several parties.

[19][20][21] This lasted until he was defeated by Antonio Hernández Mancha in the 1987 AP congress, which prompted his resignation as the party's parliamentary speaker and leader on 8 February 1987.

[5][40] Pedro Sánchez nominally re-assumed the title once he was reelected as PSOE leader in June 2017, although he did not have a seat in parliament as a result of him resigning in protest to his party tolerating Rajoy's second government in October 2016.