An average Easter egg consists of about 20% chocolate and 80% packaging, according to trading standards.
One Easter egg tested by experts in Hampshire consisted of 14% of chocolate and 86% of cardboard and plastic.
Officials said they would "be pursuing the matter" with companies in order to force them to reduce unnecessary waste.
A spokesman said: "Trading standards believes eggs are not luxury items and the packaging need not be over elaborate and must not be excessive."
Claire Wilton, from Friends of the Earth, told the BBC website: "Easter eggs are the most visible example of the problem of over-packaging.
"But the food we buy daily is all over packaged - and this has a huge impact on the environment.
"There are laws against over-packaging but the government simply doesn't enforce them in a tough enough way."