The Thunderbox Lateral (TL), also known as the Thunderbox Goldmine (LionOre) Gas Lateral), is a transmission pipeline located near Leinster, Western Australia.

The TL is owned by Northern Star (Thunderbox) Pty Ltd and operated by APT Goldfields Pty Ltd.

The TL is 23 km in length,  114.3 mm in diameter, and has a maximum capacity of 9.5 TJ/day.

The TL transports natural gas from the Goldfields Gas Transmission Pipeline to the Thunderbox Gold mine power station.

The TL is currently a non-scheme pipeline, and is subject to the access regime for non-scheme pipelines under Chapter 6A of the National Gas Access (WA) Law and Part 23 of the National Gas Rules (WA) (NGR (WA)).

The WA Economic Regulation Authority granted Category 1, 2 and 3 exemptions under Part 23 of the NGR (WA) for the TL that apply from 4 June 2022 to 4 June 2027.