Immigration New Zealand is investigating how a privacy breach, in which a couple's passports were sent to the wrong person, could have happened.
The agency says the Auckland couple's passports were sent to another client on Wednesday after all three were granted residence visas.
Its Henderson office manager Wayne Levick says the person who received the passports alerted the agency almost immediately and the passports will be back with their rightful owners by Friday.
Mr Levick says he's called the couple to apologise for the mistake, which he says is very rare.
"Over the last nine months or so we've become aware of three incidents in total. None of those incidents are acceptable but in the context of 500,000 transactions it's definitely not a commonplace event."
Immigration New Zealand general manager Nicola Hogg says the breach of privacy is extremely regrettable