Bank and building society staff are giving "inexcusably" bad information about how much of their customers' money would be protected if the provider were to go bust , an investigation by Which? has found.
The consumer group's team of researchers posed as new customers to ask 13 banks and building societies some basic questions about how the Financial Services Compensation Scheme (FSCS) works. Under the scheme, up to £85,000 of someone's savings is protected if their provider goes under.
Researchers told the providers they had £100,000 to deposit into an account. But out of the 156 anonymous calls they made across 13 providers, not one member of staff gave an unprompted warning that £15,000 of this money would not be protected in the event of a collapse.
The 13 providers contacted were HSBC, Lloyds Bank, Nationwide Building Society, Barclays, Santander, the Co-operative Bank, First Direct, Royal Bank of Scotland (RBS), NatWest, Bank of Scotland, Halifax, Britannia Building Society and Yorkshire Building Society.
Researchers then asked staff specifically about savings protection limits and found staff at Yorkshire Building Society and Halifax were the only ones able to give the correct answer each time they were asked.
One NatWest employee told a researcher: "I imagine it's like PPI. The bank wouldn't have anything to do with anything like that."
Nearly two years ago, rules came into force which mean that banks, building societies and credit unions must prominently display stickers or posters in branches to help raise consumer awareness of compensation levels.
Richard Lloyd, Which? executive director said: "It is inexcusable that bank staff can't give customers basic information about the compensation scheme if their bank goes bust.
"In the event of a collapse, this bad advice could cost people many thousands of pounds from their life savings. We hope this is a wake-up call to the banks that they need to improve staff training."
The £85,000 limit applies per banking authorisation rather than per banking brand, so if you have savings with more than one member of the same banking group, your cover may be more limited, although this is not always the case.
For example, Which? highlights that Co-operative Bank, Britannia and Smile share the same authorisation, but RBS and NatWest, which are both part of the RBS banking group, have separate authorisations.
For joint accounts, the savings compensation limit doubles to £170,000.
Which? argues that the FSCS protection rules would be much easier for consumers to understand if they applied per individual brand.
Its researchers asked bank and building society staff if having savings elsewhere affected levels of protection and found that "overall, the responses were poor".
Overall, HSBC came bottom of the Which? research, with a score of just 51% and Yorkshire Building Society came top with 88%, followed by Britannia Building Society with 82% and Halifax with 81%.
The British Bankers' Association (BBA) said it was disappointed at the findings.
A spokeswoman for the BBA said: "All employees are made aware of the FSCS and many banks have relevant training so it is disappointing that more staff did not communicate the benefits of the scheme when asked.
"The industry strives to make sure that detailed information on the FSCS is available via posters in branches, information on bank statements and marketing materials.
"The BBA will work together with the banks to look at the concerns raised in this survey to help make sure that customers are given consistent and accurate information on FSCS protection."
HSBC told Which? it will use the research to remind customer-facing staff of the FSCS protections, while the Co-operative Bank said it would welcome the opportunity to understand the findings in more detail and make improvements.
Lloyds Bank told the consumer group that it will consider what additional training may be needed and Santander said had re-visited its training to reiterate certain points.
Nationwide told the group that the majority of its staff refreshed their FSCS training in February and would be shortly followed by the remainder. It said its FSCS education takes place on an annual basis.
The FSCS recently set up an online tool to help people check that their money is protected and allows them to enter the names of their banks, building societies and credit unions.
The checker can be found at www.fscs.org.uk/protected.