The Financial Ombudsman Service (FOS) is proposing a new funding system for those businesses which receive mass complaints.
For the largest users of its services - which it defined as the "ten or so financial groups that account for over 70% of our caseload" - it proposes a new group account arrangement which would allow it to "measure more accurately the costs to the FOS of the work generated by each of these groups".
The plan is published today alongside the FOS's plan and budget for 2012/13.
The "largest users" of the FOS, which have more than 2,000 cases referred per year, will have to pay a quarterly case-related fee in advance, based on an agreed assessment of likely future use of its services.
Pro-rata adjustments would then be made, in a range of between 10% and 15%, and the fee would take into account factors such as the number of front-line enquiries the Ombudsman has handles from the business's customers.
Acknowledging that a "one size fits all" arrangement did not reflect the substantial proportion of work contributed by the larger users of the FOS, it said its plan "more accurately reflects the costs associated with each major business".
It added: "We believe that for our largest users we should move more towards a model that recognises in greater detail the actual costs associated with the work that each business and its customers generate for our service.
"At its simplest, this would involve moving towards a model that geared our charges for these businesses to an overall assessment of the costs associated with it. This means that a business that produced 10% of our work should expect to contribute around 10% of our costs."
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