Which? found that the Ferrero Rocher Collection tray was the worst offender with 42% of its total weight made up with packaging, while just 11% was recyclable.
The packaging of Thorntons Continental Selection made up 29.4% of its weight, followed by Cadbury Milk Tray on 22.6%.
However, both brands’ packaging were significantly more recyclable than Ferrero Rocher, at 87% and 93% respectively.
At the other end of the scale, Lindt Lindor Mix contained just 11.5% packaging, with only the individual chocolate wrappers not being recyclable, while Marks & Spencer’s The Big One Selection had the least packaging at 8.5%, although only 71% was recyclable.
Which? also found confusion among consumers about recycling symbols on the packaging.
Just under half (48%) wrongly identified the green dot that is regularly found on packaging as a sign that the packaging can be recycled, when it actually means that the manufacturer pays into a recycling scheme and the packaging may not be suitable for recycling.
Nikki Stopford, director of research and publishing at Which?, said: “For many of us the indulgent look of these festive chocolate boxes is synonymous with the Christmas season.
“We are more aware than ever of the impact that we’re having on the world around us so we want our research to help people to make the right choices for them and to understand how to dispose of packaging in the most eco-friendly manner.”
Ferrero said: “Ferrero Collection is a delicately created product and the packaging is of fundamental importance to protect our chocolates from damage during transport, in the shops and at home.
“The box used for Ferrero Collection can be recycled only when the local infrastructure allows to do so but in the UK this is still not available. We are aware that some consumers like to reuse the boxes in fun and creative ways like those suggested on our website.”
Thorntons said: “Thorntons Continental packaging has been updated with a new hermetic tray seal, which ensures product freshness and avoids cross flavour tainting from the most intense tastes as Espresso or Sicilian Mousse.
“We are always reviewing our product range to ensure that we offer our consumers high quality taste experience.”
A Cadbury spokesman said: “Without robust packaging, the shelf life of many products would be far shorter and could create more food waste which is 10 times more detrimental to the environment than plastic.
“We have managed to make substantial progress to minimize the environmental impact of packaging by developing products that are 100% recyclable, depending on your local recycling facilities, while also protecting the product inside and keeping it fresh.”
1. Foil wrappers can be recycled but you need to make a bundle of at least 4cm in diameter for it to be identified at the recycling centre.
2. The plastic tubs containing Celebrations, Roses, Quality Street, Heroes, Morrisons Mega Mix and Chocolate Treats by Sainsbury’s are made of PET 1. This is the same plastic that water and soft drinks bottles are made of. Easily recycled, this is collected by 99% of local authorities.
Which? surveyed 2,155 people in May.