Fraudsters stole just over $4.2 million from New Zealanders between April and June, with text message scams on the rise.

New Zealand's Computer Emergency Response Team director Rob Pope says New Zealanders lost $1.6m less than in the previous quarter, but the reason behind the drop was unknown.

In the three months to June, CERT NZ responded to 1950 reports from individuals and businesses, with 21 percent reporting financial losses.

Historically, most phishing was delivered by email, but this year CERT NZ had seen more smishing - scams sent by text message, says Pope.

The messages aim to get people's logins and passwords, which can lead to severe losses.

"The rise in SMS text-based phishing (smishing) is a worrying development. The number of phishing reports (including smishing) to CERT NZ is up 26 per cent from the last quarter and doesn't seem to be slowing down."

Smishing messages generally pretend to be from reputable organisations, such as banks and government departments.

They usually claim there is a problem and ask victims to click on a link to resolve it.

Recently, some smishing texts have come with a phone number - calling it gave scammers direct access to victims and could make scams seem more legitimate, says CERT NZ.

"The risks to people are increased with smishing, because most people have their phones on them all the time and see text messages as soon as they arrive.

"This means messages can come through at times when you aren't thinking as clearly," CERT NZ says in its quarterly report.

The best way to stay safe from scam messages is not to click on links in texts and emails.

"Even if you think the text might be legitimate, it's better to navigate to the organisation's website using another method."

CERT NZ says in the three months to June, malware reports increased 36 per cent, but scam and fraud reports were down 24 per cent on the three months prior.

Online marketplaces were frequently being used by scammers, CERT NZ said.

Some pose as buyers, pretending to purchase items from genuine sellers. The scammer often says they have paid for a courier to pick up the item and asks the seller to send them an 'insurance fee', to be refunded when the item arrives.

After scammers receive the fee, they break off all contact with the seller and cancel their purchases. It could be hard to recover funds from this type of scam, CERT NZ says.

Scammers posing as buyers are also requesting bank account details from sellers to make payments.

The scammer then asks the seller to check their email for confirmation of payment. The scammers sends an email that looks like it's from the seller's bank and claims a transaction was attempted, but could not be processed due to a limit on their bank account.

The email states the seller's 'bank account limit' can be increased by transferring money to their last buyer, the scammer. It says this will be refunded once their limit has been increased.

When the target sends through the money, the scammer immediately breaks off all communications and leaves the seller with a long fight to recover any of the money they paid.

-RNZ.