First Gas owns and operates the Maui Pipeline and its associated assets.

The Maui pipeline runs 299 km from the Oaonui Production Station (south of New Plymouth) to the Huntly Power Station (south of Auckland) in the North Island of New Zealand.

Beginning transmission in 1979, the Maui Pipeline carried 18 PJ of gas from the Maui field in its first year of operation. In 2015, the Maui Pipeline carried 143 PJ of gas from seven production stations that are directly connected. More than half of that gas goes to three consumer connections to the pipeline: the Huntly Power Station and the two methanol plants owned by Methanex.

First Gas also owns other gas transmission pipelines that are directly connected to the Maui Pipeline at 13 interconnection points. These supply major industrial plants, dairy factories and power stations throughout the North Island. Gas originally transported through the Maui Pipeline is also used to supply local low pressure distribution networks in Auckland, Wellington, Hamilton, Tauranga, and many other North Island towns and cities. These distribution networks supply gas to thousands of homes, businesses and essential services, such as hospitals.

The Maui Pipeline operates under an Open Access regime. This means that any party wishing to carry gas on the Maui Pipeline or wishing to connect to it may do so on standard terms and conditions set out in the Maui Pipeline Operating Code. There are currently 12 different parties who ship gas through the Maui Pipeline.