Keeping tabs on people with criminal convictions and tightening national security are behind measures to tighten the country's borders from next month, Immigration NZ says.

The organisation is now trying to get word about its new NZeTA requirement which takes effect from October 1.

Approximately 1.5 million people who visit from 60 "visa waiver" countries will now be required to obtain the New Zealand electronic travel authority - NZeTA - before being allowed to board a plane or cruise ship bound for New Zealand.

However, the new requirement - which costs either $9 or $12 - excludes New Zealand and Australian citizens and those who already hold a valid visa for New Zealand

The move is designed to prevent people travelling here who are considered a risk to the country's safety by identifying them well before check-in.

Authorities are looking to identify anyone previously sentenced to a term of imprisonment of 12 months or longer, those considered a threat to national security or who are members of a terrorist group. Travellers coming by air or cruise ship will be required to answer questions about any criminal convictions and the purpose of their trip.

INZ's director of policy integration Nick Aldous said visa waiver countries, those whose citizens do not need a visa to come to New Zealand, include the UK, the United States, Canada, Hong Kong, Malaysia and most European countries.

Currently visitors flying to New Zealand only receive light-touch screening at check-in, while cruise ship passengers and crew are not screened at all. But the NZeTA will give authorities early warning of individuals who potentially pose a risk Aldous says.

"In the past we have often not been aware of this until they arrive or after a plane is in the air. Now we can manage the situation earlier and avoid making decisions [on these people] on the fly."

The measure will reduce the number of those who are denied entry on arrival - 1173 last year alone - because authorities will be alerted to suspect travellers earlier.

However, to get their message across Aldous hoped ordinary Kiwis could help alert anyone they knew planning to visit the country of the new condition.

"This is a key travel time for many tourists, especially those coming to visit friends and relatives over Christmas.

"Those affected will be denied boarding if they do not hold an NZeTA so, if you've got people coming, it's important to spread the word about these new rules to ensure they get on board and their travel isn't disrupted."

An NZeTA would be valid for two years and visitors could come and go as often as they liked within that period.

While it was a traveller's responsibility to check their travel and entry requirements, Aldous said they appreciated it was a significant change for visitors.

"Based on the experience of other countries there will be a transition period before it becomes a natural process."

Aldous said the form could take up to 72 hours to process.

On average 22 per cent of travellers from visa waiver countries come to New Zealand to visit friends and relatives. The percentage is even higher for those from the UK, 46 per cent, Canada 29 per cent, and Hong Kong 25 per cent.

"Given this, it is important for Kiwis to be informed and aware of the changes."