Supermarket shoppers can pick up everything they need for Christmas dinner for eight people for less than £20 this year, a survey has found.

The cost of buying 11 Christmas dinner essentials – including a turkey, plum pudding, fresh vegetables and cranberry sauce – comes out at £19.82, or £2.48 a head, after shopping around for the best prices at Aldi, Lidl, Asda, Morrisons and Iceland, Good Housekeeping magazine found in its annual festive shopping basket cost survey.

Good Housekeeping tracked the price of the 11 products across 10 major supermarket chains and found prices were the cheapest since it began its survey eight years ago. The overall cost has dropped 10.8% since 2009, when the price for Christmas dinner was £2.78 a head.

The reduced cost of groceries at Aldi and Lidl was the main contributor to the fall in the overall price of the Christmas dinner shopping basket compared to 2015, according to Good Housekeeping.

Food prices generally have been driven down in recent years as the big four supermarkets – Tesco, Asda, Sainbury’s and Morrisons – have reacted to the rise of German discounters Aldi and Lidl with aggressive price cutting.

However, supermarkets have warned that prices are likely to rise next year as the falling value of the pound against the dollar and euro following the vote to leave the EU pushes up the price of imported products and ingredients.

Of the 11 foods tracked by Good Housekeeping to provide a Christmas meal with all the trimmings, six have gone down in price, including turkey, and three have stayed the same as last year. Only the prices of Christmas pudding and mince pies have increased, as the price of imported raisins, butter, flour and sugar has jumped since 2015, due to a combination of factors including the collapse of the pound and weaker supplies.

Aldi was the cheapest supermarket for those wanting a one-stop shop, where the ingredients for Christmas dinner for eight cost just £22.03. Aldi’s basket is 11% cheaper than last year’s winner, Iceland, which this year falls to third place (£24.81), behind Lidl in second place (£24.57). The most expensive basket was from Marks & Spencer (£49.40) followed by Waitrose (£40.02).

“Supermarket shoppers will be relieved to see Christmas essentials are still so affordable,” said Caroline Bloor, the consumer director of Good Housekeeping. “While five of the supermarkets have cheaper baskets this year, it’s mainly thanks to the big decrease in the cost of these groceries at Aldi and Lidl that the overall basket is significantly cheaper. So think carefully where you shop or you could end up paying twice as much.”

Tony Baines, the joint managing director of corporate buying at Aldi, said: “At Aldi, our customers get the same quality as M&S and Waitrose, but at prices significantly cheaper than Iceland. We know that this is more important than ever at Christmas time.”

This year’s Christmas Dinner Index, from analysts Mintec, which compares the cost of a slightly different basket of products including turkey, vegetables and pork, found that the price of the festive meal rose by 1% year-on-year and is still lower than both 2013 and 2014.

Potato prices rose 52% in the year to November, it said, as bad weather hit yields and delayed planting and harvesting, while similar conditions contributed to a 65% rise in onion prices. Parsnips were up 14%, but carrot prices were 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 sent pork prices higher by 14% year-on-year. But that was offset by a 2% drop in turkey prices, which accounts for a larger proportion of the meal and weighs more heavily on the index.

But Mintec warned shoppers that there could be further price rises ahead. “It is worth noting that prices are likely to rise in December as demand continues to increase,” it said. “So stocking up on turkey and pork early is probably the best course of action.”

Good Housekeeping’s £2.48 a head Christmas dinner: the 11 ingredients

• Turkey: Asda – £8 (2.8-4kg)
  
• Potatoes: Aldi – 29p (2kg)
  
• Stuffing mix: Asda and Morrisons – 30p (2 x 85g)
  
• Brussels sprouts: Aldi – 58p (2 x 500g)
  
• Carrots: Aldi – 29p (1kg)
  
• Parsnips: Aldi – 58p (2 x 600g)
  
• Cranberry sauce: Lidl and Asda – 55p (200g)
  
• Christmas pudding: Aldi and Lidl – £3.49 (907g)
  
• Brandy butter: Aldi and Lidl – £1.25 (200g)
  
• Mince pies: Lidl – £1.49 (12 pack)
  
• Christmas cake: Iceland – £3 (2 x 400g)
  
• Total – £19.82

Cost of a one-stop Christmas shop

• Aldi – £22.03
  
• Lidl – £24.57
  
• Iceland – £24.81
  
• Tesco – £28.08
  
• Asda – £29.68
  
• Morrisons – £31.12
  
• Co-op – £31.26
  
• Sainsbury’s – £35.40
  
• Waitrose – £40.02
  
• M&S – £49.40