Every large yacht owner has, at some point in the last two years, been asked by a broker, surveyor, or well-meaning charter guest whether their vessel is "CII compliant." The honest answer for the overwhelming majority of superyachts is that the question doesn't apply — but the confusion is understandable, because IMO's decarbonization framework has moved fast, and the tonnage thresholds that exempt most yachts aren't widely explained in yachting media.
This guide sets out exactly what CII and EEXI require, why most superyachts fall outside their mandatory scope, what the voluntary Superyacht Carbon Intensity Indicator actually is, and where the binding IMO Net-Zero Framework stands as of 2026.
Source: IMO, EEXI and CII — Frequently Asked Questions (imo.org); IMO Net-Zero Framework FAQ (imo.org); MEPC.338(76); Lloyd's Register, Superyacht Carbon Intensity Indicator (lr.org); SuperyachtNews, 13 May 2025.
What CII and EEXI Actually Are
Both instruments were adopted under MARPOL Annex VI and entered into force on 1 November 2022, becoming mandatory from 1 January 2023. They address different things and apply to different ships.
EEXI (Energy Efficiency Existing Ship Index) is a one-time technical assessment — similar in concept to the design efficiency requirement applied to newbuilds (EEDI), but retrofitted onto the existing fleet. It calculates a ship's theoretical CO₂ emissions per unit of transport work based on engine power, ship type, and size, and compares it against a required baseline. EEXI applies to ships of 400 gross tonnage and above of the ship types IMO lists: bulk carriers, gas carriers, tankers, container ships, general cargo and refrigerated cargo ships, combination carriers, LNG carriers, ro-ro ships and cruise passenger ships.
CII (Carbon Intensity Indicator) is an ongoing, annual operational rating — not a one-time design check, but a yearly measure of actual fuel consumption relative to distance sailed, adjusted for ship type and size. Ships receive an annual rating from A (best) to E (worst), and consistently poor ratings trigger a corrective action plan requirement. CII applies only to ships of 5,000 gross tonnage and above, again of the listed ship types.
Yachts are not on either list, which is why Lloyd's Register describes EEXI and CII as not yet applicable to most yachts. On tonnage alone, a vessel large enough to cross the 400 GT EEXI line is common among 70m+ superyachts. A vessel large enough to cross the 5,000 GT CII line is rare — only the very largest superyachts exceed it, such as the 156m Dilbar at 15,917 GT.
Why Most Superyachts Fall Outside CII
This is the point most owners and captains get wrong, usually because CII gets discussed in yachting press without the tonnage qualifier attached.
The overwhelming majority of superyachts — across the entire under-30m to 70m+ range typically discussed in the yachting industry — sit well below 5,000 GT. Gross tonnage is a volumetric measure, not a length measure, and yacht hull forms are far less voluminous relative to their length than cargo or passenger ships. A 70m yacht, even one built for generous interior volume, typically sits under 2,000 GT — nowhere near the 5,000 GT CII threshold.
This means: CII, as written today, does not directly apply to the vast majority of superyachts. No annual carbon intensity rating, no A–E grade, no corrective action plan requirement under CII specifically — because the tonnage gate and the ship-type list exclude them.
EEXI is a closer call on tonnage alone: many large yachts are well over 400 GT. What keeps them outside EEXI's mandatory one-time assessment is ship type, not size. Owners of very large yachts should have their naval architect or classification society confirm the vessel's ship type and GT rather than assuming exemption by length alone.
Gross tonnage and ship type, not length overall, determine whether CII and EEXI apply. Two yachts of similar LOA can have meaningfully different GT depending on hull form, superstructure volume, and interior layout. Don't estimate your exposure from LOA — get the vessel's actual GT confirmed against both the 400 GT and 5,000 GT thresholds.
If Your Yacht Is Captured by EEXI: What Compliance Actually Involves
If your classification society confirms that your vessel does fall within EEXI's scope, it helps to know what the assessment actually requires, since it's a materially lighter process than the ongoing CII rating.
EEXI is a one-time technical calculation, not a recurring annual measurement. A naval architect or class society calculates the vessel's attained EEXI value based on installed engine power, hull characteristics, and ship type, then compares it against the required baseline for that vessel category. If the calculated value already meets the requirement — common on newer or efficiently designed yachts — no further action is needed beyond the paperwork.
If the vessel doesn't meet the baseline, owners generally have two practical paths: technical modifications to improve fuel efficiency (propeller upgrades, hull coating improvements, energy-saving devices), or engine power limitation (EPL), also referred to as shaft power limitation — a verified, often software- or hardware-enforced cap on maximum engine output that brings the calculated EEXI value into compliance without requiring a full re-engine. EPL avoids the cost of a propulsion system overhaul, though it does cap top-end performance.
Either route is verified and certified by the vessel's classification society as part of the existing survey framework — it does not introduce a separate, parallel compliance regime to manage.
CII's Reduction Targets — Relevant Even If You're Exempt
For the ships CII does apply to, the annual reduction targets under MEPC.338(76) are steep, measured against a 2019 baseline:
| Year | Required reduction vs. 2019 baseline |
|---|---|
| 2023 | 5% |
| 2024 | 7% |
| 2025 | 9% |
| 2026 | 11% |
Sources: Resolution MEPC.338(76), adopted 17 June 2021 (CII reduction factors guidelines, G3); IMO: rules on ship carbon intensity and rating system enter into force (A–E ratings for ships of 5,000 GT and above; D for three consecutive years or E for one year triggers a corrective action plan).
The trajectory continues tightening under the current framework. While many superyachts sit outside mandatory CII scope, the method still signals the direction of decarbonisation policy and informs voluntary yacht-specific schemes. Confirm scope against the current resolution and vessel particulars.
The Superyacht Carbon Intensity Indicator (SCII): Voluntary, Not Mandatory
Blue ESG, with support from Lloyd's Register, developed a voluntary Superyacht Carbon Intensity Indicator that adapts CII-style carbon-intensity logic for yachts. Confirm the current eligibility criteria and programme status on the scheme owner's official page.
Source: Lloyd's Register, A greener future for the superyacht industry (20 September 2023): LR supported Blue ESG in developing the Superyacht Carbon Intensity Indicator, which assesses operational emissions against annual usage for yachts over 400 GT.
Key points about SCII:
- It is not a regulatory requirement — no flag state or IMO instrument mandates it
- It applies CII-style carbon-intensity logic (operational emissions measured against the yacht's annual usage) to a size band that CII itself doesn't reach
- Owners and yards pursue it as an opt-in market signal — a standardised metric for comparing yachts rather than a self-reported claim
- It positions vessels ahead of any future mandatory extension of carbon intensity rules to smaller tonnage bands, should that occur
For owners weighing whether to pursue an SCII assessment, the calculation is closer to a reputational and charter-market positioning decision than a compliance obligation — a genuinely different consideration than EEXI or ISM Code compliance, which are not optional where they apply.
The IMO Net-Zero Framework: Delayed, Not Cancelled
The most consequential near-term development in IMO decarbonization policy isn't CII or EEXI — it's the Net-Zero Framework, the implementation mechanism for IMO's 2023 GHG reduction strategy.
Timeline as it actually stands:
- The framework was approved at MEPC 83 in April 2025
- Formal adoption, expected via vote, was postponed by one year in October 2025
- As of October 2026, the extraordinary session that will consider adoption is due to resume on 4 December 2026, subject to confirmation at MEPC 85 (30 November–3 December 2026)
If adopted, the Net-Zero Framework is expected to apply — consistent with the existing CII precedent — to ships of 5,000 GT and above, meaning it would not directly capture the majority of superyachts in its initial form, in the same way CII does not today.
The Net-Zero Framework's one-year delay is a genuine, confirmed postponement — not a cancellation, and not a signal that IMO's decarbonization trajectory has reversed. Owners and captains should treat 2026 as a monitoring year: the resumed session on 4 December 2026 is the concrete date to watch for the framework's formal status, not a date to assume away.
What Actually Governs Superyacht Environmental Compliance Today
With CII and (for most vessels) EEXI and the Net-Zero Framework sitting outside mandatory scope, the binding compliance framework for the typical commercially operated superyacht remains what it has been: the flag state's yacht code (for Red Ensign flags, the REG Yacht Code, which replaced LY3) and, for commercial yachts of 500 GT and above, the ISM Code, alongside the parts of MARPOL Annex VI that apply regardless of tonnage — sulphur content limits on fuel, NOx emission controls in Emission Control Areas, and general pollution prevention requirements.
This matters for practical compliance planning: a captain preparing for a flag state or Port State Control inspection in 2026 should not expect a CII audit trail to be requested for a sub-5,000 GT vessel, but should expect the usual ISM Code documentation where ISM applies, fuel sulphur content records, and MARPOL Annex VI compliance records that have applied for years.
What This Means for Owners Planning Ahead
Three practical takeaways for owners and management companies thinking about 2026 and beyond:
Confirm your actual GT against both thresholds. Don't estimate exposure from LOA — get written confirmation from your naval architect or classification society of where your vessel sits relative to the 400 GT (EEXI) and 5,000 GT (CII) lines.
Treat SCII as a market decision, not a compliance one. If your charter programme or ownership positioning benefits from a standardised carbon-intensity benchmark, SCII is a credible option developed by Blue ESG with Lloyd's Register's support. If not, there is no regulatory pressure forcing the decision in 2026.
Watch the resumed session on 4 December 2026. The Net-Zero Framework vote is the single most consequential near-term regulatory event for the broader shipping industry's decarbonization trajectory — and while it's unlikely to directly capture most superyachts on adoption, the direction of travel matters for any owner planning a newbuild or major refit with a multi-decade operating horizon.
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Sources: IMO, EEXI and CII — Frequently Asked Questions (imo.org/en/mediacentre/hottopics/pages/eexi-cii-faq.aspx); IMO Net-Zero Framework FAQ (imo.org); MEPC.338(76); Lloyd's Register, Superyacht Carbon Intensity Indicator (lr.org); SuperyachtNews, 13 May 2025. Regulatory thresholds and timelines are subject to change — confirm current status and vessel-specific applicability with your classification society or flag state administration.
What changed (7 Sep 2026): Removed or marked unsupported numeric claims and replaced them with sourceable, vessel-specific guidance.
