Boeing is taking a $4.9bn hit to cover the costs of the grounding of its 737 Max aircraft after two deadly crashes.
The charge is set to wipe out profits when the world’s biggest planemaker posts quarterly results next week.
In a statement, Boeing also said its “best estimate at this time” is that 737 Max will return to service in the last three months of this year.
A crash in Indonesia in October, followed by another in Ethiopia in March, killed 346 people in total.
Boeing is facing one of the worst crises in its history after its best-selling aircraft was grounded worldwide after the disasters.
The manufacturer, facing intense scrutiny over the regulatory clearance for the aircraft to fly, has cut the monthly production rate from 52 to 42 as airlines hold off purchases.
“We are taking appropriate steps to manage our liquidity and increase our balance sheet flexibility the best way possible as we are working through these challenges,” Boeing chief financial officer Greg Smith said in a statement.
Also in the same statement, Boeing chairman and chief executive Dennis Muilenburg, said: “This is a defining moment for Boeing. Nothing is more important to us than the safety of the flight crews and passengers who fly on our airplanes.
“The Max grounding presents significant headwinds and the financial impact recognised this quarter reflects the current challenges and helps to address future financial risks.”
Boeing said it continues to work with aviation authorities to get the 737 Max back into the air, which it hopes will be in the fourth quarter of 2019.
But the statement added: “This assumption reflects the company’s best estimate at this time, but actual timing of return to service could differ from this estimate.”