Nationwide has issued a warning to its 16 million members, urging shoppers to take extra care as they could find themselves being overcharged.
With two weeks to go and spending set to surge, the bank says many people could end up paying far more than they need to if they rush to the tills.
Customers are warned about the twin dangers of falling victim to fraudsters and paying over the odds for purchases in the rush to complete Christmas shopping.
With December 25 now just two weeks away, the financial institution expects transaction volumes to surge significantly compared to last year.
More than 20 million payments are anticipated as consumers scramble to secure their festive gifts, prompting Nationwide to call for heightened awareness among shoppers.
The building society forecasts that Friday December 12, and Saturday December 13, will see approximately 20.6 million transactions processed, marking a 6.39 per cent rise on the equivalent dates from the previous year.
Activity is expected to climb even higher as the holiday approaches, with December 20 predicted to be the single busiest day.
Nationwide is alerting customers to scam alerts
| GETTY / NATIONWIDEOn that date alone, Nationwide anticipates processing around 10.7 million transactions as shoppers race to complete their final purchases before Christmas Day.
The surge in activity comes despite ongoing concerns about consumer confidence, according to the building society's analysis.
Commenting on the data, Mark Nalder, Service, Operations and Performance Director at Nationwide said: "Despite continued lower consumer confidence as we head towards Christmas, it’s encouraging to see that we’re expecting higher volumes of spending on Christmas shopping than the previous year.
"These peak periods will be incredibly busy days for retailers as consumers race to finish their shopping."
He added: "It's also more important than ever to pause and think before making a purchase to ensure that you’re paying the best price and to be on the lookout for potential scams, whether that is in-person, online shopping, or on social media.
"Platforms like Snapchat and Telegram showed the largest year-on-year increase in reported social media scams according to our data so it’s important that shoppers remain vigilant for any deals that seem too good to be true.”
The building society recommends using secure payment methods and avoiding bank transfers unless absolutely certain about the recipient.
It's more important than ever to pause and think before purchasing
| PEXELS
Customers are encouraged to report any suspicious activity to their bank or building society and to Action Fraud without delay
| GETTY / NATIONWIDECustomers are encouraged to report any suspicious activity to their bank or building society and to Action Fraud without delay.
Nationwide operates a 24/7 fraud helpline and offers a Scam Checker service, which allows members to have payments verified before they are made.
If the building society approves a transaction through this service and the customer is subsequently defrauded, a full refund is guaranteed.
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