Woolies supermarkets as well as the company's BWS, Metro and petrol outlets will stop offering free disposable plastic bags to shoppers in NSW, Victoria, Queensland and Western Australia from June 20, 10 days earlier than originally planned.
"Our teams have been working hard behind the scenes to accelerate the rollout of this plan so we can start making a positive impact on the environment as quickly as possible," chief executive Brad Banducci said in a statement on Wednesday.
"We know this is a big change for our customers and store teams, and we need to do all we can to make the transition as seamless as possible for both."
Twelve stores across NSW, Victoria, Queensland and Western Australia will get a head start by phasing out single-use plastic bags from Wednesday.
Shoppers will instead have to bring their own bags or buy reusable bags in Woolies' stores, which provide more than 3.2 billion plastic bags a year.
Tasmania, South Australia, Canberra and the Northern Territory are already subject to state-imposed bans on single-use plastic bags.
Woolworths and rival Coles last July joined the push to rid Australia of disposable plastic bags, and set a deadline of June 30 for their stores.
Environment groups Planet Ark and the Boomerang Alliance have backed the bag bans.
"Experiences in countries like the UK and Ireland have shown the introduction of small charges on plastic bags can end up reducing plastic bag usage by up to 85 per cent as shoppers embrace reusable alternatives, and we have every confidence this can happen in Australia too," Planet Ark chief executive Paul Klymenko said.
The 12 Woolworths stores phasing out plastic bags from Wednesday
NSW - Marayong, Greenway Village, Dural, Mullumbimby
VIC - Wyndham Vale, Taylors Lakes, Toorak
QLD - Mossman, Noosa Civic
WA - Singleton, South Fremantle, Cottesloe