Lloyds Banking Group, which includes Lloyds and Halifax, and RBS, which owns Royal Bank of Scotland and NatWest, issued apologies on Monday after users took to Twitter to say they were experiencing problems accessing mobile and online banking.

While services were back to normal later in the day, data shows bank IT outages can cause long-standing issues as they can affect consumers’ creditworthiness.

Research by credit checking service ClearScore found that two-thirds (64%) of consumers who checked their credit report after a bank IT failure uncovered errors that could impact their creditworthiness, including missed payments that weren’t their fault.

Only a quarter (27%) of those who had heard about a major IT outage at their bank checked their credit report for potential mistakes afterwards

Justin Basini, CEO and co-founder of ClearScore, said: “When banks suffer IT meltdowns consumers don’t just suffer the immediate inconvenience of not being able to access their account; there can also be lasting damage if payments are missed.

“It might take several weeks for a missed payment to show up on your credit report so many only found out they’ve been a victim when they’re turned down for a financial product like a mobile phone contract or a mortgage.”

How to get credit score mistakes fixed fast by Justin Basini, CEO and co-founder of ClearScore

Talk to the company

If you spot a mistake the first thing to do is let your bank or credit card provider know. They may be happy to amend it immediately or you may need to go through their official complaints procedure.

They should send updates to all the credit reference agencies they use, so you won’t have to make a request for each individual agency.

Talk to the credit report provider

Your credit score belongs to you and you have a right to ensure it’s accurate. That means you can raise a dispute if you think there’s an error.

What if the company doesn’t agree?

If you believe there’s an error on your report but you can’t get it fixed then you can add a Notice of Correction to your file. That’s essentially up to 200 words explaining what happened and why it doesn’t reflect your normal financial behaviour.

This is not just for bank errors, it can also be used to explain any negative marks on your score.  So, if you had a period of ill-health, for example, and got behind with your bills, you can leave a note to explain.