The announcement came from the Environment Minister who added the figure equated to a reduction of about 215 million bags.
The MLA for South Belfast – and Chair of the Environment – said the figures proved placing a levy on plastic bags had been the right decision for the environment.
Anna Lo MLA said: “I am delighted at reports today, signalling the vast decrease in plastic bag use across Northern Ireland.
“While some may have questioned the introduction of this levy, the results speak for themselves. Consumers across Northern Ireland have taken a large leap towards a more environmentally-friendly approach to everyday life.
“I’m glad that much of this money will be reinvested in environmental projects, with some available to support community projects. But we must do more to fulfil our green agenda and I hope the Minister will soon tackle climate change in a bid to make Northern Ireland more sustainable.”