A total of 785,000 people passed through the hub between April and September, compared with 8.4 million in summer 2019.
Before the coronavirus pandemic passenger numbers for summer 2020 had been forecast at 8.8 million.
Airport officials said they did not "expect to break even" until 2021.
Gordon Dewar, chief executive of Edinburgh Airport said he was in talks with the Scottish government about implementing testing at the airport.
He said the "ever-changing situation and near-constant changes to quarantine exemptions" meant forecasting for 2021 was "almost impossible".
It is hoped an airport testing system could stop passengers having to quarantine after entering the country.
First Minister Nicola Sturgeon said: "If we deem (it), and the advice to government is that clinically and logistically and operationally we can reduce the requirement to quarantine by introducing a testing approach instead, we will certainly be open to doing that.
"But as I have discussed in the past it is not necessarily going to be a straight swap, testing for quarantine.
"It may reduce the period of quarantine if it is deemed to be effective but it continues to be under discussion."
Mr Dewar, said: "It's been an incredibly difficult time for all of us and the scale of the recovery challenge that faces us is now really hitting home.
"We have spent years building growth in our passengers, routes and infrastructure, so to see all of that fall back is a concerning position for us to be in.
"Our business plans have been in a constant state of flux due to circumstances worsening, the introduction of and constant changes to quarantine, and of course all of this feeds into passenger confidence.
"We need to see a robust testing regime which will protect public health, provide reassurance and see travel and tourism begin to rebuild."
source: BBC News
Fewer than a million passengers travelled through Edinburgh Airport in the past six months - down 91% on the previous year.