Understanding the IMO Net Zero Framework
The International Maritime Organization (IMO) has taken a significant step toward decarbonizing global shipping. The upcoming Net Zero Framework (NZF), if adopted, will mark a historic addition to MARPOL Annex VI. It is designed to chart a pathway for reducing greenhouse gas emissions from international shipping and align the sector with global climate goals.
The Mærsk Mc-Kinney Møller Center for Zero Carbon Shipping (MMMCZCS) has examined the details, the timeline, and the process that will guide this framework from draft stage to implementation. While questions remain, the direction is clear – shipping is heading toward a more regulated and accountable era of emissions management.
The Road to Adoption
From Draft to Decision
The NZF was approved as draft amendments to MARPOL Annex VI at MEPC 83 in April 2025. The process has been unusual. Instead of the traditional consensus approach, a vote was held. Out of 103 states present, 63 voted in favor, 16 against, and 24 abstained. This outcome achieved the majority required, allowing the proposal to progress.
The next milestone is the extraordinary session MEPC/ES.2 in October 2025. This is where the adoption vote will take place. Only states that are party to MARPOL Annex VI will be entitled to vote, and the bar is higher this time – a two-thirds majority is required. With 108 contracting states covering around 95% of the world fleet, the outcome of this vote is pivotal.
Entry Into Force
If adoption takes place in October 2025, the amendments will automatically enter into force on 1 March 2027 unless a significant number of parties raise objections. This “tacit acceptance” procedure ensures that regulations are not easily stalled.
The first reporting period under the NZF begins on 1 January 2028. This is when shipping companies will be expected to demonstrate compliance, effectively turning regulation into operational reality.
Why Guidelines Matter
Closing the Gap Between Rules and Practice
Regulations such as the NZF set the direction, but guidelines are what make implementation possible. They provide the technical detail, clarity, and interpretation needed for global uniformity. Without guidelines, enforcement would be inconsistent and compliance uncertain.
Although guidelines are considered soft law, in practice they are widely adopted. They can even evolve into binding requirements after testing and refinement. For the NZF, guidelines will therefore serve as the bridge between high-level commitments and practical outcomes.
Developing the Guidelines
Guidelines for the NZF will be created through correspondence groups, which bring together member states and observer organizations. These groups work between formal IMO meetings to draft, refine, and consolidate texts. Leadership is provided either by a designated state or the Secretariat, ensuring coordination and focus.
The process is both collaborative and technical. Input from states, industry, and organizations helps ensure that the guidelines are not only legally sound but also practically workable.
The Scope of the Work Ahead
Six Categories of Guidelines
For the NZF, approximately sixteen guidelines are to be developed or revised. These can be grouped under six categories, covering everything from reporting methods to technical compliance standards. The draft work plan prepared by the IMO Secretariat sets out the timeline, with development spanning 2025 to 2027 across several MEPC sessions.
This phased approach reflects the complexity of the framework. Each guideline must be detailed enough to guide industry but flexible enough to evolve as technology, fuels, and practices change.
The Timeline
The process begins at MEPC/ES.2 in October 2025 and continues through MEPC 84, 85, and 86. By 2027, the guidelines are expected to be finalized, just in time for the first reporting period. The timing is tight, but it is designed to ensure the industry has clarity before compliance obligations begin.
Why This Matters for the Shipping Industry
Raising the Bar for Decarbonization
The NZF is more than just another regulation. It signals a step change in the way shipping addresses its climate footprint. By embedding a net zero trajectory into MARPOL, the IMO is aligning shipping with global climate ambitions.
This raises the bar for the industry, but it also creates opportunities. Companies that move early on compliance will not only avoid penalties but also position themselves as leaders in sustainable shipping.
Opportunities for Collaboration
The development of guidelines provides a chance for collaboration across governments, industry, and expert organizations. This collaboration is vital to ensure that the framework reflects both environmental ambition and operational reality. Stakeholders with expertise in fuels, technology, and compliance systems have an important role to play in shaping workable solutions.
Challenges on the Horizon
Political and Technical Complexities
While the direction is set, challenges remain. The vote in April highlighted political divisions. Some states remain hesitant about the costs and implications of stricter rules. The adoption vote in October will test the strength of global commitment.
On the technical side, the development of sixteen guidelines within two years is ambitious. The shipping industry is diverse, with fleets operating under different conditions and levels of technological readiness. Ensuring fair and practical rules will require careful balancing.
A Moment of Transition
The NZF reflects a broader shift in shipping. What was once a sector slow to regulate emissions is now becoming a focal point of global climate policy. For the industry, this means transition. Compliance will be mandatory, but leadership in this space can deliver competitive advantage.
Organizations that engage early, test solutions, and prepare for the reporting requirements of 2028 will be better placed to adapt. More importantly, they will be contributing to a cleaner and more resilient future for global trade.
Conclusion
The IMO Net Zero Framework is moving steadily from proposal to adoption, with 2025 and 2027 as decisive years. If adopted, it will mark a turning point for global shipping, embedding climate goals into international regulation.
The success of the NZF will depend on the development of detailed guidelines and the willingness of states and industry to work together. While challenges exist, the framework offers a clear path toward sustainable shipping.
For shipping companies, this is more than compliance. It is an opportunity to align with the future of transport and to demonstrate leadership in the global effort to decarbonize. By preparing early and engaging with the development of guidelines, the industry can help ensure that the NZF becomes not just a regulatory milestone but a catalyst for meaningful change.