A $2.50 surcharge will be imposed on late-night taxi fares on Friday and Saturday in an attempt to get more cabs on the road.

But fares at other times will remain frozen for a year, Transport for NSW said on Friday.

Late charge: A $2.50 surcharge will start on Friday, September 27. Credit:Andrew Quilty

The decision to hold taxi fares steady but install the late-night surcharge was a compromise by the O'Farrell government in response to a proposed overhaul of fares by the pricing regulator.

The $2.50 surcharge will start on Friday, September 27 and apply between 10pm and 6am.