The cost of Christmas pudding ingredients has soared 21% with festive foodstuffs set to climb further as demand rises in the weeks ahead.
The price of raisins, butter, flour and sugar has jumped since 2015, owing to a combination of factors including the collapse of the pound and weaker supplies, commodity data expert Mintec said.
Weaker sterling rates in the wake of the referendum have led to a 3% rise in the price of raisins, which are imported to the UK, while a drop in milk production has sent butter prices up 92% to their highest level in five years.
Higher quality wheat crops have increased the cost of flour by 19%, and low carry-over stocks from the 2015/16 season have nudged sugar prices up by 61%.
But a forecast rise in California almond production has sent prices lower by 21%, helping offset the climbing cost of the traditional Christmas dessert.
Artificial Christmas tree prices could rise, despite the relatively unchanged costs of PVC plastic, which is used for fake tree needles. It is the rising cost of metal that could influence price tags, with steel prices soaring 46% amid production cuts in China.
Meanwhile, Mintec's Christmas Dinner Index, which counts turkey, vegetables and pork, shows that the price of the main holiday meal has only risen 1% year-on-year and is still lower than both 2013 and 2014.
Potato prices rose 52% in the year to November, as bad weather hit yields and delayed planting and harvesting, while similar conditions have contributed to a 65% rise in onion prices.
Parsnips were up 14%, but carrot prices are down year-on-year thanks to lower demand in Europe, where domestic supplies were higher.
Strong demand in China and worries about lower production in the UK have sent pork prices higher by 14% year-on-year.
But that has been offset by a 2% drop in turkey prices, which accounts for a larger proportion of the meal and weighs more heavily on the index.
Turkey prices were higher in 2015 because of concerns about avian flu, Mintec said.
But there could be further rises ahead, the report warned.
"It is worth noting that prices are likely to rise in December as demand continues to increase, so stocking up on turkey and pork early is probably the best course of action."