Coles has introduced national limits on egg purchases due to a growing bird flu outbreak in Victoria.
The highly pathogenic H7N3 strain of bird flu has been detected on five farms in the state's southwest, in an effort to stop the spread of the disease.
The supermarket giant's customers in every state and territory can now only buy a maximum of two egg cartons, with the exception of Western Australia.
Coles says the limit is temporary but has not revealed how long it is expected to last.
"We are working closely with all of our suppliers to ensure eggs remain available for our customers and we are providing support to the industry in responding to the Avian Flu cases in Victoria," a Coles spokesperson said.
Woolworths does not have any limits on egg purchases and no other national stores have publicised limits.
Victoria is the third largest egg producer, churning out almost 20 per cent of the 6.68 billion eggs produced in 2022 to 2023 financial year, according to Australian Eggs.
When was the bird flu outbreak first detected?
Over the past seven weeks the virus has been detected on five farms linked to Farm Pride, Avgo, Surf Coast Eggs and another business.
The affected farms in Meredith, Lethbridge and Terang have been placed into lockdown with at least 580,000 birds euthanised.
Victoria's chief veterinary officer Graeme Cooke has said eggs and poultry products from retailers do not pose a risk and are safe to consume.
Avian influenza is a viral disease found across the globe that spreads between birds or when feed and equipment is moved between sites.
The United States has imposed restrictions on imports of Victorian eggs and poultry products.
