Shopping around for travel insurance on the high street? Make sure you visit an independent travel agent as well as one of the nationwide chains to secure the best deal. The big chains such as Thomas Cook and Going Places are charging more than double the price of many independent agents.

The Observer telephoned agents in Twickenham, Middlesex, to get a quote for two adults and two children travelling to Spain for a two-week holiday in August. Edwin Doran Travel quoted £60 for a policy (see below). Just down the road at Thomas Cook a standard policy would cost £138.

A Thomas Cook spokeswoman said: 'We never claim to be the cheapest - we are a one-stop holiday shop. Everybody sets a price that is right for their own business.' More than half of the holidays sold by Thomas Cook include free insurance but these are usually restricted to peak booking periods such as January. The spokeswoman declined to reveal how much commission the company made out of each policy sold.

Debbie Duncan-Studart, retail manager at Edwin Doran Travel, said the agency made £15 from selling a £60 policy but the mark-up by most multiples would be much higher. Edwin Doran is known for its transparency: the company charges a fee of £25 an hour for the research of a detailed itinerary which is refunded if a booking is made.

Co-op Travelcare, an independently owned chain, has been offering free insurance on summer 2001 holidays since last May. 'Throughout the year we will offer free insurance on some of our holidays even if it is just a few, selected operators,' said a spokeswoman.

Andrew Dickson, of Bolton-based St Andrews Travel Centres, said: 'We are tarred with the same brush. The multiples are bringing the whole travel agency network into disrepute.'

John Tindale of Advantage Travel Centres, a consortium representing 700 independent agents, said his members had to offer competitive policies to compete with other new entrants into the travel insurance market. 'We have to be competitive - especially now the Post Office and Tesco are selling policies,' he said.

How they compare

(Quotes based on two adults and two children travelling to Spain for two weeks this summer)

The multiples

Thomas Cook (700 shops): £138 for its standard policy, which includes up to £1 million medical expenses and £1m personal liability. Currently offering free insurance for any overseas holidays over £350 per person.

Going Places (729 shops): £147.96 for two adults and two children for the standard policy, which includes up to £1m medical expenses and £1m personal liability. Currently offering free insurance for overseas holidays over £349 per person .

Co-op Travelcare (312 shops): £140.22, which includes up to £10m medical expenses and £2m personal liability. Currently offering free insurance for overseas holidays over £345 and half-priced insurance for holidays between £195 and £345.

Small independents

Edwin Doran Travel, Twickenham: £60 includes up to £10m medical expenses and £2m personal liability.

Kitts Travel, Potters Bar: £62.88 includes up to £5m medical expenses and £2m personal liability.

St Andrews Travel, Bolton: £87.24 policy includes up to £5m medical expenses and £2m personal liability. No excess.