The 2016 Chilean municipal elections were held on 23 October 2016 to elect the mayors and municipal councillors responsible for local government in Chile's 346 communes, which are administered by 345 municipalities. Each municipality is headed by a mayor (alcalde) and a municipal council (concejo municipal) of six, eight, or ten councillors, depending on the number of registered voters in the commune. Mayors and councillors serve four-year terms and may be re-elected indefinitely.

The elections were the second held under Chile's law on automatic voter registration and voluntary voting, which replaced the earlier system under which registration was voluntary but voting, once registered, was compulsory. Turnout fell sharply from the previous municipal election, and abstention—about 65 percent of registered voters—reached a historic high for a Chilean election. The governing centre-left Nueva Mayoría coalition lost ground nationally, while the right-of-centre Chile Vamos coalition and independent candidates made gains; independent left-wing candidate Jorge Sharp also won a widely noted upset victory in Valparaíso.

Background As with previous municipal contests, the 2016 election served as a political barometer ahead of the 2017 presidential and parliamentary elections. It was also the first municipal election contested by Nueva Mayoría since the coalition's formation in 2013.

In the 2012 Chilean municipal elections, the then-governing conservative Alianza coalition suffered a heavy defeat, winning 121 mayoralties (47 for the UDI, 41 for RN, and 33 independents). It finished behind the centre-left Concertación, then in opposition, which won 167 mayoralties (56 PDC, 30 PS, 37 PPD, 13 PRSD, 27 independents, and 4 PCCh).

The National Congress debated moving the election date originally proposed by the Electoral Service (Servel), since the two days following 30 October are public holidays—the Day of the Evangelical and Protestant Churches (31 October) and All Saints' Day (1 November)—which would have created a long holiday weekend. The Chamber of Deputies approved moving the vote forward by a week to 23 October, a change approved by the Senate on 29 September 2015.

Increase in the number of councillors The number of municipal councillors to be elected increased in several communes, reflecting growth in the voting-age population, since council seats are apportioned according to the number of registered voters. Communes with fewer than 70,000 registered voters elect six councillors; those with between 70,000 and 150,000 elect eight; and those with more than 150,000 elect ten.

+ Councillor seats by communeSeats per commune2012201610 councillors17228 councillors43416 councillors285282Total communes345345Total councillors2,2242,240

Five additional communes—Iquique, La Serena, Providencia, Pudahuel, and Los Ángeles—joined the seventeen communes that had already elected ten councillors in 2012, among them Viña del Mar, La Florida, Valparaíso, Maipú, Puente Alto, Arica, Antofagasta, Las Condes, Temuco, San Bernardo, Santiago, Ñuñoa, Rancagua, Talca, Peñalolén, Puerto Montt, and Concepción.

Lists and primaries The governing Nueva Mayoría coalition initially planned to field two lists for councillor races—one combining the PDC and PS, the other the PPD, PRSD, and PCCh—while considering how to accommodate the MAS Región and Citizen Left (IC) parties. On 21 April, the MAS and IC agreed to form a third councillor list together with the PRSD.

Chile Vamos agreed on 24 November 2015 to field three separate councillor lists: one composed solely of National Renewal (RN), another of the Independent Democratic Union (UDI), and a third of Political Evolution and the Independent Regionalist Party. RN's general council had already resolved to run its own list three days earlier, a decision confirmed by its coalition partners.

Several smaller coalitions were also formed. Sentido Futuro, a centrist alliance created in September 2015 and formally launched in January 2016, ran mayoral and councillor candidates under the "Chile Quiere Amplitud" pact, all backed by the Amplitud party. A left-wing alliance, Pueblo Unido, brought together parties including Igualdad and the Frente Popular, while Unión Patriótica ran under the list "Justicia y Transparencia".

The Progressive Party (PRO) announced in March that it would field 37 mayoral candidates nationwide, and on 10 April announced a new pact with the Patagonian Regionalist Democracy and Regional and Popular Front parties. Registered on 22 July as "Yo Marco por el Cambio" and joined also by Wallmapuwen, the pact fielded 60 mayoral candidates and more than 1,200 councillor candidates.

The Liberal, Humanist, and Green Ecologist parties announced in May the creation of the Democratic Alternative pact together with the regionalist Somos Aysén and MIRAS parties. When candidacies were formalized in July, however, Somos Aysén and the Green Ecologist and Poder parties withdrew and ran separately; the latter two formed the "Poder Ecologista y Ciudadano" list, while Somos Aysén competed alone.

Revolución Democrática announced in May that it would field mayoral candidates in Antofagasta, Taltal, La Serena, San Miguel, La Granja, Santa Cruz, and Castro, as well as councillor candidates in those communes and in Santiago, Providencia, Las Condes, and Ñuñoa, running under the list name "Cambiemos la Historia".

Amendments to the primary elections law Chile's primary elections law initially required that the lists competing in mayoral elections (and therefore in any associated primaries) be identical to those competing in councillor elections, which prevented some coalitions from fielding more than one councillor list. On 24 March, the Chamber of Deputies approved an amendment allowing a single mayoral list per coalition while permitting multiple councillor lists.

The law also shortened the registration period for primary candidacies from 60 to 40 days, drawing criticism from the Electoral Service, which warned that the required administrative procedures could not be completed in the reduced time. The government subsequently sent Congress a bill to move the primary date to 19 June, which was approved and sent for promulgation on 7 April.

Ultimately, only Chile Vamos registered candidates to hold primaries in select communes. Nueva Mayoría failed to register its primary candidacies by the deadline (23:59 on 20 April) after disputes between its constituent parties over which communes should hold primaries; the party's registration was rejected by the Electoral Service on procedural grounds, excluding it from the 19 June primary process. The coalition appealed to the Election Certification Tribunal (Tricel), which on 11 May accepted the complaint, ruling that party presidents were not required to appear in person and allowing Nueva Mayoría to register its primaries.

Conduct of the primaries For the primary elections held on 19 June, 5,067,812 people were eligible to vote, of whom 4,910,988 were not affiliated with any political party, 129,082 were Nueva Mayoría members, and 27,742 were Chile Vamos members. A total of 96 primaries—53 for Nueva Mayoría and 43 for Chile Vamos—were held in 93 communes, since both coalitions held simultaneous primaries in Arica, Concón, and San Fernando.

The day before the primaries, polling-station officials were required to convene to formally constitute the receiving boards; the Electoral Service reported that only 34.3 percent of boards (1,781 of 5,193) had been constituted in time.

Preliminary results of the primary elections were as follows:

PartyVotes%CandidatesNominatedA. Chile Vamos86,438100%9943Independent Democratic Union37,33743.20%2720National Renewal26,63330.81%3215Independents18,90821.87%338Political Evolution3,1273.62%50Independent Regionalist Party4330.50%20B. Nueva Mayoría180,893100%14953Christian Democratic Party44,40324.55%3616Socialist Party of Chile40,51722.40%3313Independents37,64720.81%2710Party for Democracy24,90713.77%236Radical Social Democratic Party24,15213.35%216Communist Party of Chile8,8474.89%72Citizen Left2320.13%10MAS Región1880.10%10Valid votes cast267,33194.77%Invalid votes8,6483.07%Blank votes6,1052.16%Total votes cast282,084100%

Registered pacts After candidate registration closed on Monday, 25 July 2016, a record 19 lists had been registered for the election, the most in Chile's democratic history—eight of them fielded by the two largest coalitions, Nueva Mayoría and Chile Vamos, each of which split into four lists (three for councillors and one for mayor). The letters identifying each pact on the ballot were assigned by lottery on 28 July. A total of 1,228 mayoral candidacies and 13,327 councillor candidacies were submitted, subject to ratification by Servel's regional offices on 7 August.

PactPartyMayorsCouncillorsA. Regionalist of MagallanesRegionalist Party of MagallanesE. Nueva MayoríaB. Nueva Mayoría para ChileChristian Democratic PartySocialist Party of ChileG. Con la Fuerza del FuturoRadical Social Democratic PartyMAS RegiónCitizen LeftS. Nueva Mayoría por ChileParty for DemocracyCommunist Party of ChileC. Poder Ecologista y CiudadanoGreen Ecologist PartyPoderD. AysénSomos AysénF. Chile VamosH. Chile Vamos RN e IndependientesNational RenewalJ. Chile Vamos PRI-Evópoli e IndependientesPolitical EvolutionIndependent Regionalist PartyL. Chile Vamos UDI e IndependientesIndependent Democratic UnionI. Chile Quiere AmplitudAmplitudK. Cambiemos la HistoriaRevolución DemocráticaM. Pueblo UnidoPartido IgualdadFrente PopularN. Norte VerdeFuerza Regional Norte VerdeO. Yo Marco por el CambioProgressive PartyDemocracia Regional PatagónicaFrente Regional y PopularWallmapuwenP. Alternativa DemocráticaLiberal PartyHumanist PartyMIRASQ. Unidos Resulta en DemocraciaUnidos Resulta en DemocraciaR. Justicia y TransparenciaUnión Patriótica

Candidacies in major communes The table below lists mayoral candidates in some of Chile's most populous communes; winning candidates are shown in bold. For results in individual communes, see the regional election articles listed below.