The Edinburgh-based group had already signed up to Experian's unclaimed assets register, which attempts to re-establish contact between owners of dormant accounts and their money, but it is now stepping up its efforts to unite savers with their forgotten stash.
The UK's largest savings provider has already traced customers who had forgotten about £14.4m in Halifax accounts.
This is a third of the money Halifax is trying to return to savers. It has had most success in Scotland, where over half of all dormant accounts have been reunited with owners, while it has had least success in the west of England, where only 20% of customers have come forward.
Mike Regnier, head of savings at Halifax, said: "We are not resting on our laurels. Halifax is paying search agents, at no cost to our customers, to reunite the money with their rightful owners."
Halifax's hunt for lost savers began eight months ago when it had £44m held in dormant accounts. It was inspired to begin the search by the government, which had highlighted the issue of dormant accounts and plans to use unclaimed money to fund good causes.
Halifax says the average balance of its missing customers is £273. In the searches that have been completed, more than 5,000 customers were reunited with an average of more than £2,500 each.
A dormant account is one that has not been used for 15 years. The accounts mostly fall out of use when customers move home and forget to tell their bank.
Guardian Unlimited © Guardian Newspapers Limited 2007
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