The lotto players, from New South Wales and Victoria, won about $5.2 million each.
Lotto officials have been unable to make contact with the NSW winner, despite the entry being registered.
The entry was purchased at Narellan Newsagency and had owner David Thomsen very excited to discover the outlet had sold a winning ticket.
“Our customers will be as excited as we are and we are expecting a flurry of people checking their tickets,” he said.
“We’ve sold multiple division one winning entries over the past 36 years, but the feeling never gets old!”
The Victorian entry is unregistered, meaning officials have no way of tracing the second winner.
“There are over five million reasons why you should check your Oz Lotto tickets today,” The Lott spokesperson Lauren Cooney said.
“You may not think it’s possible you could be the division one winners we’re searching for.
"But if you purchased an entry in last night’s Oz Lotto draw that you haven’t checked yet, you’re in with a chance.”
The second ticket was purchased at Melton Lotto and TSG, in Melbourne’s west.
This story first appeared on 7NEWS and has been republished here with permission.