The constituency was created as per the Statute of Autonomy of Aragon of 1982 and was first contested in the 1983 regional election. The Statute provided for the three provinces in Aragon—Huesca, Teruel and Zaragoza—to be established as multi-member districts in the Cortes of Aragon, with this regulation being maintained under the 1987 regional electoral law. Each constituency is entitled to an initial minimum of 13 seats, with the remaining 28 being distributed in proportion to their populations (provided that the seat-to-population ratio in the most populated province did not exceed 2.75 times that of the least populated one). The exception was the 1983 election, when each constituency was allocated a fixed number of seats: 18 for Huesca, 16 for Teruel and 32 for Zaragoza.[2][3][4]
Voting is on the basis of universal suffrage, which comprises all nationals over eighteen, registered in Aragon and in full enjoyment of their political rights. Amendments to the electoral law in 2011 required for Aragonese people abroad to apply for voting before being permitted to vote, a system known as "begged" or expat vote (Spanish: Voto rogado).[5] Seats are elected using the D'Hondt method and a closed listproportional representation, with an electoral threshold of three percent of valid votes—which includes blank ballots—being applied in each constituency.[2][3][4] The use of the D'Hondt method may result in a higher effective threshold, depending on the district magnitude.[6]
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 two percent of the electorate in the constituencies for which they seek election—one-thousandth of the electorate, with a compulsory minimum of 500 signatures, until 1985—disallowing electors from signing for more than one list of candidates.[4][7][8]