Kiwi returnees will not be able to board flights home unless they've pre-booked their stay in managed isolation.
Around 30,000 people have already booked their isolation stay over the next three months, with the pre-Christmas period completely booked out.
Air Commodore Darryn Webb says travellers who arrive at the airport without a voucher will not be allowed to board their flight.
Webb says returnees should book a slot for managed isolation online before booking flights.
People will be sent a voucher after booking a slot, which must be presented before boarding their flight, a Managed Isolation and Quarantine spokesperson told 1 NEWS.
Payment is not required until after their stay.
The vouchers were made compulsory today.
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