States members in Alderney voted nine to one on banning single use plastic bags in the island.
Law officers will now draw up legislation before it goes back to the States later this year.
If approved at the final stage, it will be the first piece of legislation banning single use plastic in the Channel Islands.
It follows Alderney's commitment to the Blue Charter to protect the environment and marine life.
Representatives from across the Channel Islands signed the charter at the Wilder Islands Conservation conference in Alderney in October last year.
It is expected that the law will come into force by early 2021.