The Commerce Commission (Māori: Te Komihana Tauhokohoko) (sometimes shortened to ComCom[2]) is a New Zealand government agency with responsibility for enforcing legislation that relates to competition in the country's markets, fair trading and consumer credit contracts, and regulatory responsibility for areas such as electricity and gas, telecommunications, dairy products and airports.

[5] It considers applications for authorisations and clearances in relation to anti-competitive behaviour and mergers, in circumstances where the public benefit outweighs the harm to competition.

[6] In specific areas where it has regulatory responsibilities, such as electricity and gas, the Commission has additional enforcement powers to promote competition and protect consumers.

[8][9]: 54  The Commission was given the power of enforcing the Commerce Act's prohibitions through court proceedings, and to authorise anti-competitive behaviour and mergers in certain circumstances.

A Telecommunications Commissioner is appointed on the recommendation of the Minister of Broadcasting, Communications and Digital Media and has special responsibilities in relation to that sector.

[9]: 57  The current chairperson of the Commission is Dr John Small, appointed in December 2022 after the expiry of the three-year term of the previous chair, Anna Rawlings.

[10][11] One of the key roles of the Commission is to ensure markets in New Zealand are competitive, including by investigating anti-competitive behaviour and enforcing compliance.

[12] The Commission has a range of enforcement options including the provision of compliance advice or warning letters and by prosecuting a person or business in the High Court.

It does not include other kinds of anti-competitive behaviour such as a company taking advantage of a substantial degree of market power or resale price maintenance.

[19] As of January 2021, the Commission is seeking feedback on proposed revisions to its leniency policy to take into account the criminalisation of cartel conduct.

[9]: 60 In October 2018, new legislative provisions were introduced to enable the Commission to undertake investigations into particular markets to identify anti-competitive behaviour or other competition problems.

[21][22] The government made some initial changes in response to this study, including requiring wholesale prices to be advertised, to enable new entrants to move into the market.

The part of the Act which relates to oppressive contracts known as buy-back transactions was enacted on 14 October 2003 and was already enforced by the Commission prior to April 2005.