The total number of complaints in the UK financial industry in 2011 as a whole was about 255,000, 40 per cent more than the 180,000 complaints seen in 2010, the FOS said.

The great majority of complaints were found in payment protection insurance and banking and credit. Barclays Bank topped the notorious list in the investment category with 361 complaints, more than twice as many as “runner-up” Santander. Royal Bank of Scotland, which owns the wealth management brand Coutts, saw 152 investment complaints.

The number of complaints about Lloyds and all the other banks in the top five was dramatically lower than in the first half of 2011, when Lloyds received roughly 37,000 complaints.

“There is one reason alone why they have dropped and it is not because it is getting better,” a FOS spokesperson told this publication. “The UK regulator has put in place special measures to give the banks more time to deal with PPI complaints, and we see that they are now rising again.”

The other groups in the top five in terms of total complaints were Barclays, MBNA, RBS and Santander.

Earlier this week, Lloyds Banking Group, with brands such as Lloyds TSB, Bank of Scotland and Scottish Widows, announced that deputy chairman Glen Moreno is to retire from its board of directors in May.