A code of conduct will be signed today to curb spam email.

Legislation is also being planned this year to fine spammers.

In Britain, reports have suggested that as much as 90 per cent of all email sent is spam or other junk email while in New Zealand, the figure has been estimated at around 75 per cent.

In New Zealand the Telecommunications Carriers Forum (TCF) yesterday signed its SMS (Short Message Service, known as text messages) Anti-Spam Code.

TCF today plans to sign a comparable code for email.

Minister for Information Technology David Cunliffe told NZPA surveys suggested between 60 and 75 per cent of email received in New Zealand was spam.

"It's a significant issue. It has significant costs both for individual New Zealanders who find that up to three-quarters of their email is now spam, and for businesses who have to pay the costs of the traffic and for clearing the spam that arrives.

"It's also an annoyance and some of the spam that arrives is offensive."

Mr Cunliffe hoped to be able to introduce legislation this year that will impose fines on spammers.

Penalties and controls imposed would be in line with those overseas and would be able to be imposed on spammers operating from countries New Zealand agreed to co-operate with on spam.

Mr Cunliffe said only about 5 per cent of spam received in New Zealand originated in New Zealand.

He said the Unsolicited Electronic Messages Bill was ready for introduction to Parliament and the leader of the house had to decide on its priority.

"I'm very hopeful that it's going to be this year."

Legislation was only one part of the solution, which included filtering, email authentication and security measures.

"There is potential that unless worldwide action is taken against spam, the effectiveness of email, or ultimately the internet could be compromised."

Internet Safety Group director Liz Butterfield said it was as much the content of the spam as the volume that was concerning.

"Certainly we've had people receive even illegal images embedded in email scams and fraud schemes and that kind of thing coming via spam."

She said many internet Service Providers (ISPs) had spam filters and without them the volumes of spam email could be staggering.

"I think many people are not aware of the incredible volume of spam because they've opted into one of these filtered services.

"But for those who I know who don't have the filtering, one person came back from Christmas vacation with 4500 emails. Most of which were spam.

"It's presenting huge challenges and is a problem which needs to be controlled."

Ms Butterfield said research suggested the number of people generating spam was relatively small.