"Although we were able to have pandemic coverage as part of our policy over the past few years, the current situation with Covid-19 makes it prohibitive going forward, certainly in the short term," a spokesperson said.
The technicality, which could cost The Australian Open hundreds of millions, has been labelled "brutal" by New York Times tennis reporter Ben Rothenberg.
"The Australian Open had the incredible foresight to pay for pandemic insurance," Rothenberg wrote on Twitter.
"But it's set to expire before next year's tournament. Brutal."
Tennis Australia chief executive Craig Tiley said in May he was hopeful of the 2020-21 summer of tennis proceeding as planned, despite the growing threat of the coronavirus extending into next year.
"It will either be through crowds that are social distancing maybe only from Australia and New Zealand, or by then maybe some international crowds," Tiley told Channel 7.
"It's hard to know but we are preparing for all of that. We're also preparing to scale back if we have to but the full plan is to have an Australian Open in January and to have our lead-in events."
Tiley, the tournament director, also said the Australian Open could absorb the hit of the event going ahead without any spectators.
It comes as the US Open and the French Open continue to prepare to be staged later this year.
Roland Garros was the first grand slam to reschedule its 2020 event because of the coronavirus, moving to a September schedule.
It will be played just one week after the 2020 US Open concludes on September 13.
Wimbledon earlier this year announced that the 2020 event would not be staged for the first time since World War 2 in 1945.
Wimbledon is also set to come away with more than $200 million in an insurance payout after also having the incredible foresight to take out pandemic insurance following the SARS scare of 2002.
In figures yet to be confirmed by Wimbledon officials, the sport's most prestigious event will receive between $200m and $500m after taking out pandemic protection for more than 17 years.
According to reports, Wimbledon paid around $3 million per year as part of the policy.
"Of course we are fortunate to have insurance," All England chief executive Richard Lewis told The Times. "It helps but it doesn't solve all the problems."
The $51 million could be the best money Wimbledon ever spent while the Australian Open won't get to see a cent.