The UK is to blame for one in every 20 global spam messages, according to research from security firm Sophos.
The study ranked the UK fifth in a list of the worst-offending countries for spam in the third quarter of this year - ahead of Russia, Vietnam and Romania.
Europe was the worst offending continent, accounting for 33% of worldwide spam. The US was the top polluting country and responsible for one in five junk e-mails, pushing out 18.6% of global spam, compared to 15.2% last year, said Sophos.
"Spam is not just a nuisance, it is used by cybercriminals as a means of growing their operations," said Graham Cluley, senior technology consultant at Sophos.
"You should never even be tempted to open a spam message out of curiosity, as it can only take a second to effectively hand over control of your computer to the spammers."
Cluley said there has been a rise in social networking spam. "The widely reported 'onMouseOver' exploit creating spam tweets on Twitter, and a raft of Facebook scams have been created by spammers to generate money from survey websites," he said.
"Unfortunately, these scams continue to proliferate, with new ones springing up every day, and Facebook seemingly unable to kill them off permanently."