Warning: HSBC customers should triple check payments when transferring cash after app update – some almost sent £1,000s by mistake

Previously users entered the amount in pence but now they need to use a decimal point to enter the value in pounds AND pence. As one customer highlighted on Twitter (see below), if you'd entered that you wanted to transfer '17016', this would have been processed as '£170.16' under the old system. But under the new set-up this will be processed as '£17,016'. 

HSBC confirmed to MoneySavingExpert.com that it has rolled out an update to its UK mobile banking app in Android and iOS over the past month, which has included updating its payment format for transfers and standing orders to "bring it line with most other industry providers", as well as with what it already does for those using online banking. 

The bank adds that "thousands" took part in user testing the changes before they were rolled and that "no adverse impact was identified". But many HSBC customers say they weren't warned in advance of the shake-up and some add that they've almost transferred thousands of pounds in error. 

If you favour app-based banking, check out our guide to the Top App-based Bank Accounts. In our latest poll, Barclays and Lloyds were voted as the top apps from the traditional branch-based banks. 

'I nearly transferred £17,016 instead of £170.16'

Below is a selection of some of the tweets we've seen on the issue. The tweeter who highlighted the change to us says he mistakenly requested to transfer '£17,016' instead of '£170.16', but given he didn't have this sum in his account the transfer was "thankfully" declined. 

HSBC says it has not seen an increase in incorrect payments being made. 

How to prevent mistakes when making a digital payment

It sounds obvious but simply paying attention when you're entering key payment information will help to prevent errors from being made. However, there is a fail safe as even if you enter the wrong details, HSBC customers will still need to review a confirmation screen detailing the account the payment is going to, the amount being paid, and the timing of the payment before it's processed. So use this as your final check. 

If there are insufficient funds in the account, HSBC adds that the payment will not progress to the confirmation screen step. Banks can also set their own maximum caps on mobile app payments - HSBC's is £10,000, for example.   

What to do if you accidentally transfer the wrong amount

There is no guarantee that money can be recovered once it’s been sent but there are processes in place that could help you get your money back:  

• Contact the recipient and ask them to return the money. If it's a friend, family member or service provider, for example, contact them and explain the mistake and ask them to return the money. If this doesn't work, you should...  

• Contact your bank or building society. HSBC, for example, says it has a specific functionality to query incorrect payments on its app. When you click 'Query a transaction' you'll be routed through to a mobile chat agent who will try to help, but you can also speak to HSBC's customer services.

  HSBC says it can't recall or stop an incorrect payment once it's been sent. But under so-called 'faster payments' rules, where your bank finds evidence of a genuine mistake, it will contact the receiving bank on your behalf with a request to prevent the money being spent. As long as the recipient does not dispute your claim, you should receive a refund of the funds within 20 working days from when you notified your bank.

  Where the claim is disputed by the recipient, your final option may be taking them to court - see our Small claims court guide for more info on this but be aware there may be costs involved. If you're unhappy with how your bank has dealt with the issue you can also take your complaint to independent complaints arbitrator the Financial Ombudsman Service.