Hertz, which is approaching agencies directly, is talking about bringing brand value into a market that has little consumer appeal.
The process is in its early stages and a shortlist has yet to be drawn up. It is unclear if the incumbent, TBWA\London, will also be involved.
A spokesman for Hertz confirmed the company was talking to a number of agencies and said: "The world of travel has and is changing and we review our agency arrangements on a regular basis. It's very early stages and at the moment we are looking for an agency that is the right creative and strategic fit."
He added that Hertz was currently only reassessing its creative arrangements.
The media is held by Manning Gottlieb OMD.
The pitch will be led by Lesley Lindberg, the marketing director at Hertz.
She joined the company in July this year, filling a position that had been vacant for two years.
Over the past few years, Hertz has not had a large above-the-line presence and, according to Nielsen Media Research figures, its spend in the UK last year was less than £500,000. This will be increased substantially next year, according to the Hertz spokesman.
TBWA acquired the Hertz business following its merger with GGT in 1998, but the account has been dormant for the past two years.
UK activity this year has centred on mailing and point-of-sale activity for the Hertz tie-up with the Nectar loyalty scheme. A campaign that ran in April, created by Start, looked to promote the range of benefits to consumers through the link up. It used the strapline: "Hire at Hertz, anything else is pointless."
Hertz competes with Avis, the largest car rental group in Europe, as well as Eurocar and online brokers such as Holidayautos.com, which is owned by Lastminute.com.