With 98% of the ballots counted, 62% of voters rejected the proposal with 38% voting in favor, according to the Chile Electoral Service.
The new constitution would have provided full gender parity, added designated seats for indigenous representatives, and increased environmental regulations.
The constitution currently in place was written under the dictatorship of Augusto Pinochet, who ruled the country from 1973 to 1990.
On Saturday night ahead of the opening of polls Sunday morning, Chilean President Gabriel Boric tweeted, “In Chile, we resolve our differences with more democracy, never with less. I am deeply proud that we have come this far.”
The proposed change was initiated in 2020 when then-president Sebastien Piñera called a referendum on creating a new constitution amid social turmoil and popular discontent sparked by a metro fare increase in October 2019.
In October 2020, more than 78% of Chilean voters approved a plebiscite that proposed constitutional change, and in June 2021, they cast their ballots again to pick the members for a constituent assembly.
The Constitutional Assembly was the first in the world to have full gender parity and the first in the country´s history to include designated seats for indigenous representatives.
Supporters were hopeful its progressive stance would be reflected in a new, updated constitution.
And the constitutional process itself was praised internationally for giving the country an institutional way out of a social crisis, and for responding to modern Chileans’ demands for more equality and a more inclusive and participatory democracy.
After much deliberation, the final draft of the revised constitution was submitted to Piñera’s successor, leftist Gabriel Boric, in July this year.
But although most Chilean voters supported the idea of constitutional change back in October 2020, divisions appeared over the proposed draft.
Soon after the draft was made public, different polls began showing an increasing trend toward the rejection of the charter, with the government publicly recognizing that scenario.
The defeated constitution would have one of the most progressive in the world, giving the state a front-line role in the provision of social rights.
The draft put a strong emphasis on indigenous self-determination and on the protection of the environment, and would have dismantled the highly privatized water rights system. It had required gender equality in all public institutions and companies, and enshrined the respect for sexual diversity. It also envisaged a new national healthcare system.
But the project became bitterly divisive.
The right argued the draft would shift the country too far left, or that it was too ambitious and difficult to turn into efficient laws. In the lead-up to the vote, even some of its supporters on the left wanted adjustments made, with their slogan “approve to reform.”
Images from the country’s capital Santiago on Sunday show a sombre mood among supporters of the constitution, while others celebrated the news it had been voted down.
CNN’s Michelle Velez, Daniela Mohor W. and Jorge Engels contributed to this report.