Uber saw annual losses balloon to $4.5bn last year though its performance improved in the final quarter of 2017, the ride-hailing app revealed.
The 61% increase in losses for the fast-expanding and controversial company came at the same time as revenues surged by 85% to $37bn.
The figures cover a troubled year for the company as it faced sexual harassment claims and saw the departure of senior executives including its boss, co-founder Travis Kalanick, and a battle to continue operating in London.
For the last three months of the year, Uber was in the red by $1.1bn, down from $1.46bn a year earlier in a boost for new chief executive Dara Khosrowshahi.
He is aiming for Uber to make an underlying profit by next year, ahead of a planned stock market flotation.
The company’s efforts to ramp up its marketing costs in the US last year – in a bid to repair its tarnished image and fight off increasing competition – helped deepen 2017’s losses.
Comparisons with 2016 were also affected by the sale that year of its business in China resulting in a substantial gain.
Fourth quarter figures for 2017 showed an improvement thanks to better control of costs such as advertising and customer support.
A spokesman said: “We’re incredibly encouraged by our financial performance and excited by our long-term potential to serve riders, drivers and cities.”
In Britain, Uber was stripped of its Transport for London licence last September.
TfL cited concerns over its approach to reporting serious criminal offences, how it obtains drivers’ medical certificates, how criminal record checks are carried out and the use of technology which allegedly helps it evade law enforcement officials.
Uber is continuing to operate in the capital pending an appeal against the decision which is due to be heard in the spring.