Drop attributed to a decrease of consumers making phone calls.
UK operators experienced a 2.3 per cent annual revenue decrease to hit €5.3 billion in Q4, according to Telecompaper.
This was due to the rise of consumers opting for messaging and data services, which have restricted the use of the lucrative phone call platform.
Meanwhile, the UK's mobile SIM base rose by 362,000 in Q4 to 76.2 million, a rise of 863,000 from 2010.
Everything Everywhere was highlighted as the market leader with 35 per cent of all customers, which is likely down to its ownership of both T-Mobile and Orange.
Additionally, O2 and Vodafone followed, while 3UK trailed with ten per cent of the market.