SSE has outperformed other electricity and gas providers and been awarded a five-star rating in Consumer Focus's latest complaints league table.
The supplier has topped the ranking for the third successive quarter after recording the lowest number of customer complaints in the three months to December 2011.
Consumer Focus calculates table positions based on the number of times consumers contact Consumer Direct, Consumer Focus and the Energy Ombudsman over issues in relation to the supplier's market share.
SSE, which has around ten million customer accounts for gas, electricity and other services, is the only provider to have been given a five star rating since the table was launched in April 2010.
Director of customer service Tony Keeling says the firm is "proud" of the achievement, adding SSE believes "the way complaints are handled is a clear measure of the value a company places on its relationship with the people who matter most - customers".
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