More than 1,300 Which? members who invest their money with investment supermarkets gave scores based on how satisfied they are with their provider and how likely they are to recommend it to a friend or family member.

Hargreaves Lansdown – Britain’s biggest fund supermarket, with 600,000 plus customers – was the only provider to secure a customer score of more than 70 per cent.

It scored 76 per cent, seven percentage points ahead of its nearest rival, Interactive Investor and eight ahead of Alliance Trust Savings. Charles Stanley Direct and The Share Centre rounded off the top five, each with a customer score of 66 per cent.

High street banks offering investment platform services performed the poorest, with Halifax Sharedealing scoring just 45 per cent, Barclays scoring 47 per cent and Natwest scoring 49 per cent.

Which? members were asked to rank providers on customer service, administration, information on investment opportunities, online services as well as value for money.

Hargreaves Lansdown was the only group to score top marks for all categories.

This is the second such accolade for the group this year.

In February, it was named Britain’s best investment platform following a study by platform comparison site The Platforum.