The airline introduced the policy in February but gave a six month grace period to passengers in the outer islands while the government's National ID Card programme was being rolled out.
Air Vanuatu's communications manager, Paul Pio, said he was confident most passengers would have some form of photo ID from next month.
They could use the National ID Card, the Vanuatu National Provident Fund (VNPF) card, a passport, school ID or a company card, Mr Pio said.