But Brits will primarily use their phones for research and not payments.
New research from Deloitte says ten per cent of all in-store UK sales will be influenced by smartphones this December, with the devices acting as decision-making tools for $3.5bn worth of transactions.
However, that doesn't necessarily mean money in the bank for retailers, as consumers will primarily use their phone to research prices, store Christmas shopping lists and engage with friends and family using social media rather than make payments directly through the devices.
The influence aspect is set to account for £3.2bn of in-store Christmas sales, while £330m of sales made directly through smartphones and £500m in sales will be made via tablets.
Meanwhile, online retail is expected to grow by 17 per cent this Christmas, with total UK retail sales growing by one per cent. This supports data from comScore that shows Black Friday online spending passed $1bn for the first time ever.
Ian Geddes, UK head of retail at Deloitte, said: "Shoppers are responding to those retailers that combine the right products with exceptional customer service across all channels, dynamic and exciting online and mobile sites and a brand that they want to be associated with and invest in."
Colin Jeffrey, head of multichannel retail at Deloitte, added: "As with recent years, the strongest growth will be found online, with purchases completed on mobile phones double or even triple that of last year.
"Retailers without flexible collection options and mobile services are failing to meet basic customer expectations and will suffer as a result. The rapid adoption of tablets and the high number received as gifts this Christmas will drive a sharp increase in transactions through these devices.
"However, whilst transaction growth is slower for smartphones, their broader influence is far greater. Whilst we forecast 10% of in-store sales will be influenced by smartphones in December, by 2016 we predict this figure will be as high as 18% for the full year, equivalent to £43bn of sales.
"We are also beginning to see the power of social commerce with more and more consumers using Twitter and Facebook to share reviews, offers and product information. Retailers are also starting to use social media as a forecasting tool, monitoring buzz around certain products to predict demand."