At Woolworths there is a one-pack limit on toilet paper and bulk or multipacks of still water and a two-pack limit on the following:

The limits apply in all of Queensland and parts of northern NSW at stores in Ballina Fair, Ballina River Street, Byron Bay, Cabarita, Casino, Goonellabah, Kingscliff, Lennox Head, Lismore Central, Lismore Square, Mullumbimby, Tweed Heads, Tweed City.

"As floods continue to ravage the east coast, critical supply lines into northern NSW and throughout Queensland have been impacted by road closures, limiting how quickly we can get stock into flood affected regions," said Woolworths Director of Stores, Jeanette Fenske.

"We have contingency plans in place and are doing everything we can to safely get stock into our stores via alternative road routes. We know the coming days are expected to bring more extreme weather as rain travels south and we will continue to monitor the situation closely, planning ahead for potential disruptions in NSW."

At Coles, more than 60 stores in Queensland including Toowoomba, Gladstone and Rockhampton and 14 stores in NSW including Lismore are effected.

A purchasing limits apply for:

"Coles' supply chain team is working hard to renew regular deliveries to our stores in flood affected areas as soon as transport routes are reopened and it is safe to do so," a Coles spokeswoman said.

"We are also working with emergency services, state governments and our logistics partners to assess other available methods to resupply stores that remain inaccessible by regular means, and to coordinate donations of food and other essentials for distribution to people in need.

"We know this extreme weather event is not over yet and our team is continuing to work to support our suppliers, growers and producers to overcome supply disruptions so shelves can be filled as soon as possible."