Guernsey's first island-wide election is set to be held on 17 June 2020.
The date has been approved by the island's government, but legislation changes are needed to create one single electoral district for all 38 seats.
Currently the 38 deputies are elected from seven districts with each district electing five or six deputies each.
The new system was chosen by a majority of 52% in the island's first ever referendum, which saw a 45% turnout of those on the electoral roll.
Politicians also agreed to change legislation to lower the minimum age for candidates from 20 to 18. The voting age in Guernsey has been 16 since 2007.
Advanced polling is also due to be introduced next year alongside improvements to the postal voting system.
The States also agreed to the creation of a new electoral roll and additional powers for the registrar-general of electors.
The legal changes will need to come back to the States for approval.