Uber reported a $US5.2 billion ($7.7 billion) loss and revenue that fell short of Wall Street targets on Thursday as growth in its core ride-hailing business slowed, sending its shares down 6 per cent.

Uber chief Dara Khosrowshahi. Credit:Michael Nagle

Uber's net loss, up from a loss of $US878 million a year earlier, reflected $US3.9 billion of stock-based compensation expenses related to its IPO earlier this year, and Wedbush analyst Ygal Arounian said its loss before interest, tax, depreciation and amortisation was in line with Wall Street targets.

Still, he said, "So far, mostly everything is below expectations."

The figures caught investors off guard because smaller rival Lyft on Wednesday had raised revenue expectations and described an easing price war, sending up shares of both companies during regular trade on Thursday.