Luxury purchases such as caviar, hand-carved smoked salmon and white truffles helped it book a 16 per cent rise in like-for-like sales in the five weeks to 1 January.
Online sales grew 22 per cent, peaking on 12 December, and made up 34 per cent of all Fortnum’s sales over the festive period.
The company’s flagship store in London’s Piccadilly saw footfall increase by 10 per cent and, on the Saturday before Christmas, a record 27,000 customers flocked through its doors.
Scots-born boss Ewan Venters said: “At the end of a year of great financial uncertainty and upheaval, these are very encouraging results.
“Our excellent Christmas performance is a reflection on the improvements we have made in our offering across online and our range of stores, and is testament to the enduring appeal of great products and impeccable service.
“At a challenging time for all retailers, we have shown that a quality experience is still highly attractive to customers around the world.”
New figures from Worldpay on Friday show that “Brexit tourists” cashing in on the battered pound injected some much-needed Christmas cheer into the British high street with a “massive” surge in spending.
Last year Venters warned that prices will begin to rise in 2017 year as a result of the collapse in sterling, stating that there is “no avoiding” shop price inflation and rising costs.