Election Resources on the Internet: Elections to the Portuguese Assembly of the Republic

Portugal held an early parliamentary election on Sunday, January 30, 2022. A description of the proportional representation system used since 1975 to elect members of the national unicameral legislature - the Assembleia da República or Assembly of the Republic - is presented here.

The official Legislativas 2022 website has 2022 election results in Portuguese. National- and district-level results are available here (and also in CSV format) for the following Assembly elections:

The election statistics presented in this space come from official data files originally issued by the Secretariado Técnico dos Assuntos para o Processo Eleitoral (STAPE) of the Ministry of Domestic Affairs of Portugal, and results published on the Legislativas 2009, Legislativas 2011, Legislativas 2015 and Legislativas 2019 websites. Note that these statistics do not include results in the election districts established for Portuguese voters residing abroad.

The Parliament of the Portuguese Republic consists of a single chamber, the Assembleia da República or Assembly of the Republic, composed of 230 members directly elected by universal adult suffrage for a maximum term of four years. Assembly members represent the entire country, rather than the constituencies in which they were elected. Governments require majority support in the Assembly in order to remain in office.

Each one of Portugal's eighteen administrative districts, as well as each one of the country's two autonomous regions - the Açores (Azores) and Madeira - is an electoral constituency. Portuguese voters residing outside the national territory are grouped into two electoral constituencies - Europe and the rest of the world - each one of which elects two Assembly members. The remaining 226 seats are allocated among the national territory constituencies in proportion to their number of registered electors.

For the 2002, 2005 and 2009 legislative elections, Assembly seats were distributed in the following manner:

Constituency	Seats

	2002	2005	2009

Aveiro	15	15	16
Beja	3	3	3
Braga	18	18	19
Bragança	4	4	3
Castelo Branco	5	5	4
Coimbra	10	10	10
Évora	3	3	3
Faro	8	8	8
Guarda	4	4	4
Leiria	10	10	10
Lisboa	48	48	47
Portalegre	3	2	2
Porto	38	38	39
Santarém	10	10	10
Setúbal	17	17	17
Viana do Castelo	6	6	6
Vila Real	5	5	5
Viseu	9	9	9
Açores (Azores)	5	5	5
Madeira	5	6	6
Europe	2	2	2
Outside Europe	2	2	2

Total	230	230	230

Political parties and party coalitions may present lists of candidates. The lists are closed, so electors may not choose individual candidates in or alter the order of such lists. Electors cast a ballot for a single list. The seats in each constituency are apportioned according to the largest average method of proportional representation (PR), conceived by the Belgian mathematician Victor d'Hondt in 1899. Although there is no statutory threshold for participation in the allocation of Assembly seats, the application of the d'Hondt rule introduces a de facto threshold at the constituency level.

To illustrate the functioning of the system, the allocation of seats in the district of Santarém for the March 2002 legislative election is presented here in detail. In the election, the following lists contested the district's ten Assembly seats:

To calculate the number of seats each list was entitled to receive, the votes polled by each of these were divided by 1, 2, 3, and so on until the number of seats to be allocated was reached, as detailed below:

Division	PS	PPD/ PSD	PCP- PEV	CDS- PP	B.E.	PCTP/ MRPP	PPM	MPT	POUS	P.H.

1	93,168	92,551	20,727	20,392	6,763	1,453	901	610	583	502

2	46,584	46,275	10,363	10,196	3,381	726	450	305	291	251

3	31,056	30,850	6,909	6,797	2,254	484	300	203	194	167

4	23,292	23,137	5,181	5,098	1,690	363	225	152	145	125

5	18,633	18,510	4,145	4,078	1,352	290	180	122	116	100

6	15,528	15,425	3,454	3,398	1,127	242	150	101	97	83

7	13,309	13,221	2,961	2,913	966	207	128	87	83	71

8	11,646	11,568	2,590	2,549	845	181	112	76	72	62

9	10,352	10,283	2,303	2,265	751	161	100	67	64	55

10	9,316	9,255	2,072	2,039	676	145	90	61	58	50

Seats	4	4	1	1	0	0	0	0	0	0

Seats were then awarded to the lists obtaining the largest quotients or averages (shown in bold). As indicated, the PS won four seats, the PPD/PSD four, the PCP-PEV one and the CDS-PP one. The seats won by each list were awarded to the candidates included therein, according to their ranking on the lists: therefore, the first four candidates on the PS list were elected to the Assembly, as were the first four candidates on the PPD/PSD list and the candidates at the top of the PCP-PEV and CDS-PP lists, respectively.

The apportionment of constituency seats can also be obtained by dividing the votes for each ticket by the smallest quotient used to allocate seats, disregarding the remainders. For the election in Santarém, the votes obtained by each list would be divided by the tenth largest average - 20,392 votes - with the following results:


PS:	93,168 20,392	=	4	seats

PPD/PSD:	92,551 20,392	=	4	seats

PCP-PEV:	20,727 20,392	=	1	seat

CDS-PP:	20,392 20,392	=	1	seat

B.E.:	6,763 20,392	=	0	seats

PCTP/MRPP:	1,453 20,392	=	0	seats

PPM:	901 20,392	=	0	seats

MPT:	610 20,392	=	0	seats

POUS:	583 20,392	=	0	seats

and

P.H.:	502 20,392	=	0	seats

As such, the smallest quotient used to allocate seats is also the effective representation threshold, that is the number of votes necessary to secure one seat. For the Santarém district, this threshold amounted to 8.4% of the vote.

The allocation of Assembly seats in Santarém shows that the lack of a statutory threshold is of little importance: since each constituency returns an average of ten seats, the effective representation threshold - the number of votes needed to secure a seat according to the application of the d'Hondt rule - becomes a significant barrier for participation in the proportional allocation of Assembly mandates.

For the 2002 legislative election, the allocation of Assembly seats by the largest average method produced the following effective thresholds:

Constituency	Seats	Average Threshold

		Votes	%

Aveiro	15	21,346	5.8
Beja	3	17,906	21.8
Braga	18	21,201	4.7
Bragança	4	15,018	17.7
Castelo Branco	5	18,383	15.4
Coimbra	10	19,186	8.2
Évora	3	19,823	21.8
Faro	8	17,525	9.4
Guarda	4	17,489	17.3
Leiria	10	20,225	8.5
Lisboa	48	22,036	1.9
Portalegre	3	15,501	22.6
Porto	38	22,736	2.4
Santarém	10	20,392	8.4
Setúbal	17	19,519	4.9
Viana do Castelo	6	16,373	11.8
Vila Real	5	20,315	15.9
Viseu	9	21,803	10.4
Açores (Azores)	5	13,578	15.1
Madeira	5	16,764	13.4

The largest average method tends to favor the major parties, with greater intensity as the constituency size diminishes: the effective representation threshold, as a percentage of the total vote, increases as the number of seats to be allocated decreases. This tendency is compounded by the cumulative effect of the application of the d'Hondt rule over a substantial number of small-sized constituencies, albeit in a rather limited fashion: most Assembly members are elected in large or middle-sized constituencies, which guarantees a generally proportional outcome. Nevertheless, in the thirteen Assembly elections held since 1975, the top two lists - especially the majority list - have been consistently over-represented in the Assembly, while the smaller parties and coalitions have been - with some exceptions - slightly under-represented.

Since the April 25, 1974 Carnation Revolution - in which a military uprising overthrew the right-wing authoritarian regime that had been in power since 1926 - Portugal has developed a party system centered around five major political forces: the Socialist Party (PS), the Social Democratic Party (PPD/PSD; originally the Popular Democratic Party), the Portuguese Communist Party (PCP), the Popular Party (CDS-PP; previously the Social Democratic Center Party) and - since 1999 - the Left Bloc (B.E.), an electoral coalition of three far-left parties.

Initially, this multi-party system did not foster governmental stability: between 1976 and 1987, there were no less than ten constitutional governments. However, since the 1987 and 1991 legislative elections, Portugal approximates a two-party system in which the PPD/PSD - a right-of-center party despite its name - and the PS have been alternating in power. The PPD/PSD ruled with an absolute majority in the Assembly of the Republic from 1987 until 1995, when the PS won the legislative elections and formed a minority government that remained in power until the 2002 legislative elections, in which the PPD/PSD prevailed by a relatively narrow margin and formed a coalition government with the CDS-PP, a right-wing, Christian democratic-oriented party. However, in 2005 the ruling center-right coalition was overwhelmingly defeated by the Socialist Party, which for the first time in Portuguese history obtained an absolute majority of seats in the Assembly of the Republic.

In the 2009 legislative elections, the Socialist Party lost the absolute majority it had attained in 2005; nonetheless, it retained the largest number of seats in the Assembly and remained in power under a minority government.