The US network launch comes after its acquisition by US-based HomeAway last year and is a major step in the firm's plan to launch a global marketplace for holiday home rentals.
Holiday-Rentals' US network has four sites - HomeAway.com, GreatRentals.com, CyberRentals.com and A1Vacations.com - and claims a combined reach of 25 million people a year.
Advertisers will be able to publish and manage their ads in the US from their existing Holiday-Rentals.co.uk account.
Holiday-Rentals.co.uk is also planning to launch a European network early next year. The network consists of Holiday-Rentals.co.uk, HolidayRentals.fr, FeWodirekt.de and newly launched HomeAway.es.
The shared inventory of the network will reach 100,000 holiday homes by the end of this year, and Holiday-Rentals.co.uk also plans to roll out a number of European web sites throughout 2007.
Alexis de Belloy, managing director of Holiday-Rentals.co.uk, said: "The US Network is a major step forward for Holiday-Rentals.co.uk and is just the first of a number of projects that will take the 'rent by owner' market to the next level. Holiday-Rentals.co.uk and HomeAway are leading the way."