Australia’s new mandatory merger control regime – are you ready for it?

Australia’s new mandatory merger control regime commenced on 1 January 2026, pursuant to the Treasury Laws Amendment (Mergers and Acquisitions Reform) Act 2024. It replaces the previous voluntary system and is designed to identify and prevent anti-competitive acquisitions – for example, deals that reduce the number of competitors or change how remaining competitors compete.

Under the new regime, if your acquisition meets the notification thresholds, you must notify the Australian Competition and Consumer Commission (ACCC) unless an exemption applies. You cannot complete the deal without ACCC approval or a notification waiver. Non-compliance can render the acquisition automatically void and lead to significant penalties.

The regime covers acquisitions of shares, assets or interests (including land) with a material Australian connection where a notification threshold is met, or the deal falls within a targeted class.

Currently, the only targeted class is supermarket acquisitions. Additional targeted notification rules apply to acquisitions by the major supermarket groups (Coles and Woolworths), regardless of the general notification thresholds.

The notification thresholds are set by Ministerial determination and are based on Australian revenue and/or the global transaction value.

Most thresholds apply from 1 January 2026, with certain asset and voting power thresholds starting on 1 April 2026. The thresholds will be indexed annually, starting from 1 January 2027.

• Large merged firm threshold. Notification is required if the combined Australian revenue of the parties is at least $200 million and either: (i) the target’s Australian revenue is at least $50 million, or (ii) the global transaction value is at least $250 million.
• Very large acquirer threshold. Notification is required if the acquirer group’s Australian revenue is at least $500 million and the target’s Australian revenue is at least $10 million.
• Creeping or serial acquisitions thresholds. If the parties’ combined Australian revenue is at least $200 million, notification is required where at least $50 million of relevant acquisitions have been made over the past three years. If the acquirer’s Australian revenue is at least $500 million, the three-year cumulative trigger is $10 million. Certain previous acquisitions are excluded (including already-notified acquisitions (other than creeping/serial acquisitions), those below $2 million, some assets no longer held, non-control share acquisitions and acquisitions not connected with Australia).
• Asset acquisition thresholds (from 1 April 2026). Some asset acquisitions that are not of all or substantially all of the assets of a business will require notification from 1 April 2026, where the combined Australian revenue of the parties is at least $200 million and the global transaction value is at least $200 million, or where the acquirer group’s Australian revenue is at least $500 million and the global transaction value is at least $50 million.
• Voting power moves (from 1 April 2026). Some shareholding “voting power” moves will require notification from 1 April 2026, such as moving from 20% or below to more than 20% in certain unlisted companies (not widely held) or moving from 20%-50% to 50% or more in any company. Where the target is a Chapter 6 entity (typically listed companies and unlisted public companies with more than 50 members), acquisitions must be notified: (i) if the acquirer already had control and voting power increases from 20% or below to more than 20%, or (ii) if the acquirer did not already have control and voting power increases from below 20% to 50% or more

Certain acquisitions are exempt from notification, even if a threshold is met.

• Share acquisitions. Some share deals where the acquirer does not obtain control of the target or where the acquirer already controlled the target before the acquisition are exempt. Where the target is a Chapter 6 entity (eg a listed company), acquisitions that result in voting power of 20% or less are not required to be notified.
• Land exemptions. These include land acquisitions in the ordinary course of business, residential property development, acquisitions by property developers, lease extensions and renewals and sale-and-leaseback arrangements.
• Financial market exemptions. These include rights issues, share buy‑backs, dividend reinvestments, FX contracts, certain derivatives where the acquisition does not result in control, and acquisitions connected with debt instruments, money lending, financial accommodation, enforcement of security interests, custodial or depository services, or clearing and settlement facilities.
• Other exemptions. Further exemptions apply where the acquisition relates to external administration and other statutory appointments, superannuation fund mergers and changes of trustee, and acquisitions that occur by operation of law.

A notification waiver is an optional, fast and low‑cost route for straightforward, low‑risk acquisitions. If granted, it removes any obligation to notify. It is not a precursor to notification, nor a clearance pathway for matters raising material competition issues. The ACCC aims to decide waivers quickly, and must determine applications within a maximum of 25 business days.

Some practical points for businesses:

• Do not lodge a waiver and a notification in parallel. Once notified, the acquisition is “stayed” until the notification is decided, so a waiver has no practical effect.
• Expect limited back‑and‑forth – provide sufficient detail upfront to show why a waiver is suitable.
• A bidder in a competitive process will generally not be able to notify until there is sufficient mutual intention with the vendor. Some bidders may seek a waiver in limited cases (for example, surprise hostile takeovers), including on a confidential basis.

Notified acquisitions are first assessed in Phase 1, which lasts up to 30 business days. The earliest approval can occur is 15 business days after the effective notification date. Most acquisitions are expected to be approved in Phase 1.

After approval, completion must wait 14 calendar days from publication of reasons to allow for any Australian Competition Tribunal review applications.

Approvals “stale” after 12 months if the acquisition is not put into effect, requiring re-notification.

If the ACCC considers the acquisition could be likely to substantially lessen competition, it may require a further in-depth Phase 2 assessment. Only a small number of matters are expected to require Phase 2. Phase 2 lasts up to 90 business days, unless extended.

Fees apply to notification waivers, notifications and (where applicable) Phase 2 reviews and public benefit applications. As at 1 January 2026:

• the fee for a notification waiver is $8,300; and
• the fee for a notification application (Phase 1) is $56,800.

Small businesses with aggregated turnover under $10 million may be eligible for a fee exemption in some circumstances.

1. Review and map upcoming transactions. Assess your M&A pipeline – particularly 2026 deals – to determine if they will meet the new mandatory notification thresholds, and consider timing implications if notification and approval is required.
2. Track serial acquisitions. Keep a rolling three-year log of relevant acquisitions (including connected entities), noting the exclusions (eg acquisitions below $2 million) and the $50 million / $10 million cumulative triggers.
3. Prepare for increased compliance costs. Plan for significant filing fees – even for a notification waiver – and increased up-front documentation.
4. Initiate early engagement with the ACCC. The ACCC encourages pre-notification engagement for all complex or potentially notifiable deals, even before formal submission.
5. Adjust deal structures and contracts. Update contracts to account for the new, longer and more rigid mandatory notification and approval timelines, and make ACCC approval a key condition precedent.

This article provides general commentary only. It is not legal advice. Before acting on the basis of any material contained in this article, seek professional advice.

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