The free market was in full swing on New Year's Eve, with the newly legalised ride sharing service Uber charging passengers up to eight times normal rates for a ride home.

Uber's Facebook page was flooded with complaints on Friday from New Year's Eve passengers who were charged up to hundreds of dollars more than usual to get home from the city after a night watching the fireworks.

Skye Shanahan of Quakers Hill told Fairfax Media she ordered an Uber ride from the North Sydney foreshore to Blacktown - a fare that would typically cost less than $100. She ended up paying $720, more than a week's rent, after a surcharge multiple of eight was applied to her fare.

"I was really excited to use Uber because the fares are meant to be cheaper.