Lloyds Banking Group has disclosed that an additional 80,508 customers may have had their financial details exposed due to an IT glitch in March, bringing the total number of potentially affected individuals to over half a million.
The banking giant has now paid out more than £200,000 in compensation.
The incident on 12 March initially impacted 446,915 customers across Lloyds, Halifax, and Bank of Scotland, who either saw other people’s transactions or had their own data shared.
The newly identified group comprises joint account holders with some of these customers.
Although these 80,508 people did not log into the banking app during the glitch, their transaction details could have been viewed.
In a letter to the Treasury Committee, Lloyds stated: "We also issued an alert on the app home screen to these 80,508 joint account holders, with a small number of exceptions based on particular customer circumstances. In notifying these customers, our focus has been on providing reassurance and support."
The bank confirmed it has paid £201,000 to 5,250 people, alongside an additional £62,000 in "goodwill" payments to 1,625 individuals since 24 March .
But the lender revised down how many people had been initially affected after logging into the app to 446,915, down marginally from 447,936 initially, due to duplication.
It confirmed 107,937 people clicked on other people’s transactions when they became visible, lower than the first estimate of 114,182.
They therefore may have been shown more detailed information such as account details, national insurance numbers and payment references.
But Lloyds stressed it had not seen an increase in daily levels of fraud against those impacted since the tech blunder on March 12.
The group highlighted the personal data of individuals who were not Lloyds group customers had also been visible, but that it had not received any complaints relating to customers of other banks.
The group said it had not yet found any customers who have suffered financial loss as a result of the incident.
“Accordingly, we have not made compensation payments on this basis,” it said.
“Separately, it is our existing practice that we may make goodwill payments for distress and inconvenience in individual cases, for example where there has been a direct impact on an individual.”
Lloyds said last month the incident was caused by a “software defect” from an overnight IT update.
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