Clydesdale Bank have apologised to customers who did not receive their festive salaries and benefit payments following thousands of complaints about glitches with online banking.

Customers of Clydesdale and sister bank Yorkshire Bank hit their social media teams with complaints of problems with wages, claiming to have not been paid and are now stuck in an overdraft with bills to pay.

Clydesdale later said the problem was believed to be caused by an incorrect date on a Bankers' Automated Clearing Services file which causes a delay in transactions showing in customers accounts.

"We are now working to get account balances updated overnight so that the correct funds are available from early [Saturday] morning," it said.

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"We want to reassure customers concerned about potential charges as a result of the current issue. Customers will not be negatively impacted financially and we will make good on any charges automatically generated. We are sorry for any inconvenience customers are experiencing."

It comes just a couple of days after thousands of customers of Lloyds Banking Group, which includes the Bank of Scotland, were unable to access internet and mobile banking services on New Year's Day because of a system outage.

Thousands across all three retail banks under the group’s banner — Halifax, Bank of Scotland and Lloyds — were affected for nearly eight hours from about 4am on Wednesday.

Website Downdetector, which tracks complaints that services are not functioning, showed thousands of issues about Yorkshire Bank - a division of Clydesdale Bank - from 3am yesterday (Friday) and well into the evening.

The peak of the issues came at 9.06am, with the site showing 410 complaints against the service, 67% related to online banking, 19% to mobile banking, and 13% to payment cards.

The Herald: Clydesdale Bank in Workington will shut by the end of June. Credit: Google Maps

The Downdetector outage maps shows central Scotland, the Midlands, Yorkshire and London amongst the worst areas hit.

Clayre McVey from Edinburgh was one of those who took to social media to complain.

"Absolutely appallling that you've waited till almost midday to announce this," she told Clydesdale. "I hope you are handing us some kind of compensation.

"It's almost 3pm and still no money in my account. I have a toddler to feed and bills to pay, just like everybodye else. This is utterly unacceptable."

Virgin Money, which owns both banks, had earlier said they were investigating the reports as a priority after initially suggesting customers should contact their employers.

In a Twitter statement the banks said said: "We are aware of the issues some customers are having with transactions coming in to their accounts.

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"We are doing a full investigation and ask that you please bear with us whilst we find out what is causing this. Any further information will be provided as soon as we have it."

Consumer group Which? estimated last year that banks are suffering IT failures at a rate of more than one a day.

Jenny Ross, money editor of the consumer organisation said the latest issues were not acceptable.

“Our research has found banks are being hit by almost daily IT failures, which can leave customers without wages and struggling to make essential payments like rent or bills," she said.

"With banks increasingly moving customers online, more needs to be done to ensure that their systems are robust enough to prevent hugely disruptive outages."

“It is unacceptable that these glitches are still so common across the industry, and banks must ensure their customers aren't shut out of making payments as a result.

"Consumers have made it clear that cash is a vital back-up when digital systems fail – so government must urgently intervene with legislation to protect access to cash for as long as it is needed."

Banks have come under increased scrutiny over IT issues after TSB’s botched migration to a new IT system in 2018. The tech failure cost the bank over £300m, led to an exodus of 80,000 customers, and provoked an inquiry by MPs and the regulator.

The Treasury select committee said in October that there was an “unacceptable” level of IT failures among banks.