Hertz is running a couple of decent promotions at the moment which are worth a look if you are planning to hire a car, either for business or over the May holiday weekends.
The first promotion is for Virgin Atlantic Flying Club, earning 2,000 miles per rental. To quote from their email:
Earn up to 2,000 Flying Club miles with Hertz
Need to rent a car in the UK once you’ve stepped off your Virgin Atlantic Little Red flight? Hertz are offering Flying Club members UK car rental from just £20 a day, plus the opportunity to earn double miles. To enjoy this great offer, simply book before 30 June 2013 quoting CDP 708870 and PC 180994 for rental before 18 July 2013
Despite the mention of Little Red, this seems to apply to rentals from any UK Hertz location.
The American Airlines AAdvantage promotion is also generous, although it depends how much you are planning to spend.
As per this link, you will earn 6 American Airlines miles for every $1 equivalent you spend at Hertz, based on a 5+ day rental. (1-4 day rentals earn 4 miles per $1.) The promotional code will also discount your rental, although whether you will really save the 35% quoted is debatable. This deal runs until 31st August.
If you are renting from Avis, this promotion for Club Carlson, the hotel programme, is also attractive and runs for all of 2013. To quote:
7,500 Club Carlson Points for Avis Rentals. Now through December 31, 2013, Avis is offering a total bonus of 7,500 Club Carlson Gold points and a 25% discount to members on qualifying car rentals of 3 or more days at participating locations in the U.S., Canada, Mexico, Latin America and the Caribbean, Australia, New Zealand, Europe, Africa, Asia and the Middle East. Make your reservation here and use coupon #MUHA018 and present your Club Carlson number at the time of reservation or at the rental counter to earn your bonus points. This offer is in addition to your everyday savings of up to 25% when you use AWD #G639300.