Cadbury has been voted the UK's happiest brand, followed by British toilet roll company Andrex and search engine Google.
Fairy detergents and Nivea took fourth and fifth place, followed by YouTube and Amazon, while Mars, Walkers and Heinz completed the top 10, the poll for advertising agency Isobel found.
Meanwhile, the bottom 10 of the 100-strong ranking was littered with political parties, banks and the airline Ryanair.
The survey asked consumers to identify brands they thought were optimistic or pessimistic, playful or boring, happy or sad and whether or not they were trustworthy and generous.
The study also measured respondents' speed of reply to questions to gauge an emotional or subconscious response.
While YouTube was identified as one of the UK's happiest brands, fellow social media giants Facebook and Twitter only made 72nd and 74th place respectively.
British Airways was voted the UK's most trusted airline but Virgin Atlantic was the happiest, in 29th place, while Ryanair in 97th place was above only the Conservatives, RBS and the Liberal Democrats.
Northern Ireland, Scotland and Wales voted differently for the happiest brand, choosing Amazon, Cadbury and Nutella respectively.
"And so that brand will be better liked, better recalled and chosen more often. So a happy brand will be a successful brand."
He added: "Political parties are not usually intrinsically happy units and their low score here reflects that. Party politics are losing relevance for many as they become less central to our sense of identity.
"Despite much advertising aimed at the emotions, the banks are all in the bottom quarter of the ranking, with only around 33% of respondents believing they are trustworthy. Perhaps there is an opportunity for a brave brand here."
The top 10 happiest brands according to the Isobel index are:
:: Cog Research surveyed 1,250 UK adults online in December.