Congress has 350 members elected from fifty-two constituencies (the fifty provinces and two autonomous cities) using closed list D'Hondt proportional representation.

[4] As a result of the 2019 general election, there were 168 female deputies or 48% of all members, making Spain the European country with the highest percentage of women in parliament, surpassing Sweden and Finland.

The Spanish Constitution establishes that the deputies are chosen by universal, free, equal, direct, and secret suffrage.

A strictly proportional system would result in fractional seats; the D'Hondt method resolves this by favoring parties receiving larger votes.

In March 2011, the Electoral Act was modified to require parties that are not represented either in Congress or in the Senate to collect signatures to support their candidacy to be able to run in the election.

One-tenth of a percent of those registered to vote in a constituency are required to be on the ballot and each citizen can sign only once for a party candidacy.

The deputies' term of office finishes four years after their election or when the Cortes are dissolved, which can take place jointly or separately with the dissolution of the Senate.

Exercising the autonomy recognised by the Constitution to the Congress of Deputies, the house is regulated by some internal rules established by itself in 1982 and it configures different government bodies to carry the pertinent competencies out.

[9] The President of the Congress of Deputies is the highest authority and it represents the House and it is, de facto, the whole parliament leader.

The ordinary sessions take place during the two meeting terms: September to December and February to June.

The extraordinary sessions are convened at the request of the Prime Minister of Spain, the Permanent Council or the absolute majority of the house.

The Plenary of the Congress can confer upon them full legislative power in relation to a matter, so they can approve or reject any bill.

It is responsible for safeguarding the powers of the house between the legislative sessions (January, July and August) or when their term has finished because of termination or dissolution.

The relief on the facade by sculptor Ponciano Ponzano centers on a sculpture of Spain embracing the constitutional state, represented by a woman with her arm around a young girl.

Surrounding the pair are figures that represent in allegorical form Justice and Peace, Science, Agriculture, Fine Arts, Navigation, Industry, Commerce and so on.