The reported loss for the full-year ending 30 September compared with a £430 million profit in 2019.
However, the airline said with its "unmatched network, leaner cost base, most trusted brand and strong liquidity, after raising more than £3.1 billion to date", easyJet is "strongly positioned to be a leader in the recovery of the European airline".
Passenger numbers for the period decreased by 50% to 48.1 million (2019: 96.1 million), with capacity decreasing by 47.5%.
Load factor "only decreased by 4.3 percentage points" to 87.2% due to a "prudent approach to capacity".
Total revenue decreased by 52.9% to £3.1 billion (2019: £6.39 billion).
Johan Lundgren, easyJet chief executive, said: "I am immensely proud of the performance of the easyJet team in facing the challenges of 2020.
"We responded robustly and decisively, minimising losses, reducing cash burn and launching the largest cost out and restructuring programme in our history – all while raising more than £3.1 billion in liquidity to date.
"EasyJet has not only withstood the impact of the pandemic, but now has an unparalleled foundation upon which to emerge strongly from the crisis. Our unmatched short-haul network and trusted brand will see customers choose easyJet when returning to the skies.
"While we expect to fly no more than 20% of planned capacity for Q1 2021, maintaining our disciplined approach to cash generative flying over the winter, we retain the flexibility to rapidly ramp up when demand returns.
"We know our customers want to fly with us and underlying demand is strong, as evidenced by the 900% increase in sales in the days following the lifting of quarantine for the Canary Islands in October. We responded with agility, adding 180,000 seats within 24 hours to harness the demand.
"And last week we saw the welcome news about a possible imminent vaccine roll-out.
"I would like to thank everyone at easyJet for their work which has left us well positioned and expecting to bounce back strongly."
EasyJet added it had been operating since March 2019 "such that it is ready for all possible Brexit outcomes".
"We are structured as a pan-European airline group with three Air Operator Certificates based in Austria, Switzerland and the UK. Around 45% of our equity capital is held by qualifying European nationals."
The airline said it expected the package holiday market would recover more quickly than flight-only bookings "and many customers will seek a package deal that provides them with more certainty in the current environment".
"Our summer 2021 booking position is significantly ahead of previous years at this point," said the statement.
"Many of our competitors are under pressure, with traditional tour operators struggling due to their large fixed cost base and financial obligations. Many online travel agents (OTAs) have struggled to cope with the customer service levels required during Covid-19 and a number of smaller travel companies have failed."
