IMO approves draft global carbon pricing system for shipping

The International Maritime Organization approved draft rules for the first-ever global carbon pricing system for shipping, with a carbon tax beginning in 2028. Backed by 63 countries including India, the framework imposes emissions costs on large vessels, reshaping a hard-to-decarbonize global industry.

The International Maritime Organization approved draft rules for the first-ever global carbon pricing system for shipping, paired with a mandatory marine fuel standard, finalized at the 83rd Marine Environment Protection Committee session in London. The package aligns with the IMO's net-zero-by-2050 goal and is expected to be formally adopted in October 2025, take effect in 2027, and include a global carbon tax beginning in 2028. Rules target large ships over 5,000 gross tonnage, responsible for approximately 85% of international shipping emissions, with a carbon fee starting at $100 to $380 per tonne of excess emissions.

Operators of large vessels over 5,000 gross tonnage are directly affected, required to cut greenhouse gas fuel intensity over time or pay a carbon fee or switch to cleaner fuels, with emissions measured on a well-to-wake basis. The vote passed with support from 63 countries including India, China, and Brazil, while oil-exporting nations such as Saudi Arabia, UAE, and Russia opposed and the United States abstained. MARPOL Annex VI currently has 108 Parties covering 97% of world merchant shipping tonnage.

Affected shipping operators should monitor the implementation timeline: final adoption of MARPOL Annex VI amendments in October 2025, approval of implementation guidelines at MEPC 84 in spring 2026, entry into force in 2027, and the carbon tax taking effect in 2028. Revenues from the accompanying Net-Zero Fund will support clean-tech R&D, green port infrastructure, maritime decarbonization in developing countries, and capacity building. The levy could generate $30-40 billion by 2030, helping close an investment gap UNCTAD estimates at $8-28 billion annually for new vessels.

Key figure — Carbon tax range: $100 to $380 per tonne of excess emissions, starting 2028