The new sites are manned by over 220 new hires, the business said.
The online marketplace will continue to operate as an independent business unit.
Amazon, Woolworths and Wesfarmers make the list.
Wesfarmers is expected to fall down the list this year following the demerger of Coles.
Retail conglomerate expecting to post earnings of between $385 million and $400 million at half year results.
Wesfarmers shareholders have approved the $20 billion demerger.
Wesfarmers shareholders meet later today to cast their vote on the proposed $20 billion demerger.
The key details around its planned $20 billion demerger of Coles are expected to follow.
The supermarket's food and liquor segment recorded sales growth of 2.1 per cent.