The telecommunications industry is banding together to combat scammers and provide more consumer protection.
The Telecommunications Forum's draft Scam Calling Prevention Code was already being implemented by Spark, which was stepping up the anti-scam programme it had been running for a few years.
The code offers a framework for the efficient sharing of information between the telcos, which is currently ad hoc and informal.
It sets out a consistent approach for the companies to identify and block scam calls between networks in New Zealand and from overseas.
The code also permits the sharing of information with third parties, including government agencies, online safety organisations and police.
Spark Home, Mobile and Business acting chief executive Grant McBeath said the formal sharing of information between the telecommunications companies would speed up the overall response to scams, but would not stop the calls from coming.
Consumers also needed to be vigilant and report incidents, he said.
"Even if we manage to reduce scam calls significantly through this new partnership, some scam calls will still get through. Ultimately, we need every individual to know what to look out for."
Consumers should avoid calling back unrecognised international numbers, and hang up if the call did not appear to be genuine, Mr McBeath said.
"Spark will never contact you out of the blue and ask for your personal information."
The company had set up a website for consumers to report scam calls.