LONDON (Reuters) - Allowing customers to take their bank account number with them would encourage more Britons to switch to a rival lender, Britain's financial regulator said on Thursday.
Such flexibility has long been a feature of the mobile phone market where customers keep the same telephone number when they shop around between rival providers.
The idea is being discussed to help boost competition in high street banking which is dominated by the "Big Five" banks, Lloyds, RBS, HSBC, Barclays and Santander.
Banks have said so called account number "portability" would be costly but the idea now has the support of the Financial Conduct Authority (FCA).
"The FCA found that being able to keep bank account details increases consumer confidence in the bank account switching process," it said in a statement.
"A significant number of individual and small business customers would be more likely to switch if they could retain their account details," it added.
Customers can already move their account to another bank within seven days, although they have to take a new account number.
The new Payment Systems Regulator, set up by the government to increase competition and innovation in payment systems, will consider the FCA's evidence.
UK junior finance minister Andrea Leadsom has been a supporter of account number portability, telling Reuters last month it could be introduced in stages.
"The FCA also found that account number portability could make switching accounts even easier. We expect the new Payment Systems Regulator to consider these findings as part of its wider work programme," Leadsom said in a statement on Thursday.
The FCA said more can be done in the meantime to improve switching, such as targeted marketing campaigns.
"We now expect the banks to deliver these improvements without delay, and we have given the regulators powers to force appropriate action should they fail," Leadsom said.
Reporting by Huw Jones; editing by Keith Weir