Money: When the car conks out, who will you call?

There can be nothing more frustrating than being stuck on a motorway hard shoulder on a bank holiday with a car full of screaming kids and an overheating radiator. The RAC says it came to the rescue of 6,500 stranded motorists during last year's spring bank holiday.

"A few minutes under the bonnet before you set off can save unnecessary time at the roadside and pounds in your pocket," says Alistair Cheyne of the AA. "It's the simple things like batteries and tyres that are letting people down. Batteries rarely last longer than four years, so replacing them near the end of their life can save a lot of time and inconvenience."

Three-quarters of the UK's 30.5 million motorists now take out some form of breakdown cover. Statistics from the breakdown companies suggest it is well worth paying for. For example, last year the AA carried out 4.3 million rescues, and one in seven of the call-outs were to fix faulty or flat car batteries. Tyre problems also proved deflating for AA members, accounting for over 211,000 call-outs.

In days of old, the knights of the road mostly arrived in familiar AA or RAC colours. Now there's a range of gallants to come to your rescue, although the AA and RAC still have the greatest share of the market. The AA, with 9.4 million customers, has 44 per cent and the RAC has around 25 per cent of the market with 5.7 million customers. Their nearest rival, Green Flag, has 3.5 million members. Direct Line is the highest-profile new entrant, offering comprehensive UK breakdown cover for pounds 58 a year; the AA charges pounds 120 and the RAC pounds 114 for equivalent cover. Direct Line launched its policies in May 1998 and has attracted 140,000 customers.

Clubs and associations can be even cheaper. The Guild of Experienced Motorists offers breakdown cover to its members for just pounds 41.50 a year. GEM was set up to promote road safety and currently has 60,000 members. To join you need a full, clean driving licence.

The Environmental Transport Association offers four levels of cover to members, starting at pounds 23 a year plus a pounds 20 annual membership fee. ETA was launched in 1990 to work with transport and environmental groups. It campaigns for a sustainable transport system in Britain and has 20,000 members.

If you buy a new car, it's likely that the manufacturer will offer free cover for at least a year. Twelve manufacturers, including Peugeot and Saab, now offer free cover from the AA. Another 12, including Ford and Renault, give free cover from the RAC. When these deals end, typically after one, two or three years, you are offered a discount on your annual premium - currently 25 per cent with the AA.

Breakdown companies now offer far more than roadside repairs. Depending on how much you are prepared to pay, they can provide overnight accommodation and a hire car to continue your journey.

There are usually very few restrictions on who can join breakdown organisations, but watch out for exclusions if your car is more than 10 years old. Green Flag, for instance, charges an extra pounds 12.50 a year. Most schemes include all or some of the following features:

n Home assistance - if your car breaks down either outside your home or within a one-mile radius of your home.

n Roadside assistance - help and repairs (you may have to pay for parts) wherever you break down in the UK, as long as you are away from home.

n Recovery - transporting your car to a local garage and you and your passengers back home or to your destination.

n European cover - assistance, recovery and spare parts, accommodation, car hire, legal costs and returning a car to the UK if you break down.

Working out which cover is the best value for money is not so simple. The levels of service vary greatly and insurers obscure their costs by offering different types of package from their competitors, making direct comparisons difficult. Europ Assistance currently offers the best deals. Its UK Driver Assist policy - covering roadside assistance, recovery and home assistance - costs pounds 35.

Standards of service can also be hard to judge. You can only really go on the statistics quoted by the companies. Both the AA and RAC have their own rescue patrols, which allow them to guarantee to be on site in under an hour. The average response time for the AA is 35 minutes, and the RAC 37 minutes. Rival firms have far fewer vehicles and have to rely on local contractors, though this doesn't appear to hinder them: Britannia Rescue and Europ Assistance currently have the fastest average response time at 33 minutes. However, speed of response can be misleading as local contractors may not be able to do any roadside repairs. They will often just tow your vehicle to a nearby garage.

n Contacts: AA, 0800 444999; Britannia Rescue, 0800 591563; Direct Line Rescue, 0181-686 9555; ETA, 01932 828882; Europ Assistance, 01444 442211; GEM, 01342 825676; Green Flag, 0800 000111; RAC, 0800 550550; Zurich Municipal, 0800 445588.

ROAD RESCUE

Cost of home assistance, roadside assistance and recovery cover

AA pounds 120

Britannia Rescue pounds 86

Direct Line pounds 58

ETA pounds 66

Europ Assistance pounds 35

GEM pounds 41.50

Green Flag pounds 72

RAC pounds 114