People are being warned about a "particularly sophisticated" email tax scam circulating.
The Inland Revenue Department (IRD) said it had received about 120 calls in the last 12 hours about the scam.
"It is a phishing scam where people get an email that looks like it's from Inland Revenue and also a form that looks very convincing," IRD said in a statement.
"The email says the recipient has a tax refund waiting for them and that they need to update their financial information in order to receive their refund."
The email address appeared as "Inland Revenue Department" but was actually sent from IRDxxxxx@s1.nzr.review.
"The address is false, but looks convincing to the lay person's eye," the statement said.
IRD urged recipients not to open the attachment.
People who had already clicked on the form and submitted any personal or credit card data should contact their bank immediately.
They were also recommended to contact IDcare at www.idcare.org or phone 0800 201 415.
People can also email phishing@ird.govt.nz to notify IRD.