Yorkshire Building Society has acquired the savings and mortgage business of Egg Banking.
The move means Yorkshire will take over the Egg brand from Citigroup and assume control of its £2.5 billion savings book and £430 million mortgage book.
Iain Cornish, Yorkshire Building Society chief executive, said he is looking forward to welcoming Egg's customers.
"Continuing to provide them with the outstanding service, administration and value that they have been used to, and which is consistent with our own approach, will be a priority for us and we will work closely with Egg to ensure that customers are kept fully informed throughout this transfer process," he added.
Yorkshire Building Society is the UK's second largest financial institution of its type with assets of more than £30 billion and approximately 2.6 million members.
Joining forces with Egg will mean Yorkshire members benefit from a wider range of products and further innovation.
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