The latest research from messaging system supplier Ipswitch has found that a massive 95% of all e-mail received is spam.
This compares with 70% in the same period last year and shows growth for the fifth quarter in a row.
The most prevalent forms of spam are those offering medication, which accounted for a quarter of all spam messages with pornography, gambling and phishing e-mails representing 12%, 17% and 12% respectively.
Clive Longbottom, service director at analyst company Quocirca, said spam is showing no sign of being beaten.
He warned that "there are signs that a higher degree of spam is now coming from groups such as organised crime, rather than individuals out for a quick win, and this type of approach needs to be stopped before it really take hold."