Regulatory guides for the fleet office.

Applies to

Ships ≥ 5,000 GT calling at EU/EEA ports (since 2018); from 2025 also general cargo ships 400–5,000 GT and offshore ships ≥ 400 GT (reporting only)

Gases

CO₂; CH₄ and N₂O from reporting year 2024

Responsible entity

The shipping company, meaning the registered owner by default or the ISM company by mandate

Data

Fuel consumed per fuel type, distance, time at sea, cargo carried / transport work, per voyage and per year

Verification

An accredited verifier assesses the monitoring plan and verifies the annual emissions report

Document

Document of Compliance issued and carried on board (by 30 June)

How it works

Each ship keeps a monitoring plan describing how fuel, distance, time and cargo are measured. Emissions are monitored per voyage and at berth, then aggregated into an annual emissions report that an accredited verifier checks. The verified report is submitted early in the following year. Since the ETS started, aggregated company-level data derived from it has become the basis of the allowances a company must surrender.

Ships of 400–5,000 GT that entered the scope in 2025 (general cargo and offshore ships) only report for now; whether they join the EU ETS is a matter for the Commission's review, with a possible inclusion from 2028 onward.

Key dates

• 1 Jan 2018Monitoring starts for ships ≥ 5,000 GT calling at EU/EEA ports
• 1 Jan 2024CH₄ and N₂O added to monitoring; MRV becomes the data basis for the EU ETS
• 1 Jan 2025General cargo ships 400–5,000 GT and offshore ships ≥ 400 GT start monitoring (reporting only)
• 31 Mar each yearVerified emissions report for the previous calendar year
• 30 Jun each yearDocument of Compliance on board for the previous reporting period

What it means for the fleet office

MRV is only as good as the daily fuel chain. Fuel per type and voyage has to reconcile with ROB and bunker delivery notes, and port-call times must be consistent because the same figures feed the EU ETS and FuelEU. A monitoring plan describes the method; the daily reports provide the evidence.

How MATS relates

Applies to

Cargo and passenger ships ≥ 5,000 GT since 1 January 2024; offshore ships ≥ 5,000 GT from 1 January 2027

Coverage

100% of emissions between EU/EEA ports and at berth in EU ports; 50% of emissions on voyages to or from non-EU ports

Gases

CO₂ since 2024; CH₄ and N₂O from 1 January 2026

Phase-in

Surrender for 40% of 2024 emissions (in 2025), 70% of 2025 emissions (in 2026), 100% from 2026 emissions onward (surrendered from 2027)

Deadline

Allowances surrendered by 30 September each year

Responsible entity

The shipping company, either the registered owner or mandated ISM company, attributed to an administering authority in a Member State

How it works

Verified MRV emissions are the starting point: after the report is verified (by 31 March), the company surrenders the corresponding number of allowances in the Union Registry by 30 September. The phase-in means that in 2026 a company surrenders allowances for 70% of its verified 2025 emissions; from 2027 the obligation covers 100% of the previous year's emissions.

Two things change with the 2026 reporting year: methane and nitrous oxide count towards the obligation alongside CO₂, and 2026 is the first year whose emissions will be surrendered in full. The Commission is also reviewing the maritime ETS in 2026, including whether to extend it to ships below 5,000 GT (but not below 400 GT) and how to reflect developments at the IMO.

Who ultimately bears the allowance cost is contractual. Time-charter ETS clauses are now common, but the legal surrender obligation remains with the shipping company.

Key dates

• 1 Jan 2024Maritime emissions enter the EU ETS
• 30 Sep 2025First surrender, covering 40% of verified 2024 emissions
• 1 Jan 2026CH₄ and N₂O included in the obligation
• 30 Sep 2026Surrender for 70% of verified 2025 emissions
• 1 Jan 2027Offshore ships ≥ 5,000 GT included
• 30 Sep 2027Surrender for 100% of verified 2026 emissions

What it means for the fleet office

Allowance exposure per voyage depends on the port pair (EU–EU or EU–non-EU), fuel per type and, from 2026, methane and N₂O factors. A clean voyage and port-call structure in the daily reports makes the ETS figure defensible and a charter-party ETS clause easier to settle.

How MATS relates

Applies to

Cargo and passenger ships ≥ 5,000 GT from 1 July 2026; offshore ships from 1 January 2027

Coverage

100% of emissions on voyages between UK ports (including round trips from the same port) and while in UK ports; 50% for voyages between Great Britain and Northern Ireland; international voyages 0%

Gases

CO₂, CH₄ and N₂O

Responsible entity

The registered owner by default, or the ISM company under an approved written agreement

Periods

First scheme year 1 July – 31 December 2026; calendar years thereafter

Deadlines

Emissions monitoring plan application within 42 days of the first maritime activity; annual report by 31 March; surrender by 30 April. The 2026 and 2027 scheme years are both due 30 April 2028

How it works

The mechanics mirror the EU scheme but run as a separate system: the ship operator applies for an Emissions Monitoring Plan with the regulator, has its annual emissions report verified by a UKAS-accredited verifier, and surrenders UK allowances in the UK ETS Registry. Port stays in UK ports count whether the neighbouring voyages are domestic or international; international voyage legs themselves do not count.

Exemptions include non-commercial government activities, fishing vessels and specified Scottish ferry services. With the scheme in place, the separate UK MRV regime has been withdrawn. Negotiations on linking the UK and EU emissions trading systems are ongoing; until a link is in place, UK and EU allowances are separate instruments.

Key dates

• 1 Jul 2026Domestic maritime enters the UK ETS (ships ≥ 5,000 GT)
• Within 42 daysApplication for approval of the Emissions Monitoring Plan after the first maritime activity
• 1 Jan 2027Offshore ships included
• 31 Mar 2027Verified emissions report for 1 July – 31 December 2026
• 30 Apr 2028Surrender for the 2026 and 2027 scheme years
• 30 Apr each yearSurrender for the previous scheme year (from 2029 onward)

What it means for the fleet office

A ship trading both to the EU and within the UK now carries two scope rules on the same voyage data: an EU port pair counts for the EU ETS, a UK domestic leg counts for the UK ETS, and port stays count in each. Per-leg accounting avoids both double work and double counting.

How MATS relates

Applies to

Cargo and passenger ships > 5,000 GT calling at EU/EEA ports, from 1 January 2025

Coverage

100% of the energy used between EU/EEA ports and at berth in EU ports; 50% on voyages to or from non-EU ports

Reference

91.16 gCO₂e/MJ, the 2020 fleet-average well-to-wake GHG intensity

Targets

−2% 2025–2029 · −6% 2030–2034 · −14.5% 2035–2039 · −31% 2040–2044 · −62% 2045–2049 · −80% from 2050

Penalty

€2,400 per tonne of VLSFO-equivalent energy deficit (41,000 MJ per tonne), increased by 10% for each consecutive non-compliant period

Flexibility

Bank a surplus for the same ship, borrow from the next period (10% surcharge, limits apply), or pool across ships, including ships of other companies

How it works

FuelEU is energy-based. For every fuel used in scope, the energy (from the fuel's lower calorific value) and its well-to-wake emission factor determine the ship's yearly GHG intensity, which must stay under the limit for the period. The annual cycle runs from the FuelEU report to the verifier by 31 January through verified compliance balance by 31 March and pooling, banking or borrowing decisions by 30 April. Penalties are paid and the FuelEU Document of Compliance is issued by 30 June. The document must be on board when calling at EU ports.

The first compliance period (2025) closed with FuelEU reports due 31 January 2026, verified balances by 31 March 2026 and the first FuelEU Documents of Compliance by 30 June 2026.

Two further obligations sit alongside the intensity limit. From 1 January 2030, container and passenger ships at berth in TEN-T core network ports must connect to onshore power supply (or use approved zero-emission technology), extending in 2035 to other ports where OPS is available, with exemptions such as stays under two hours. And renewable fuels of non-biological origin (RFNBOs) are rewarded with a multiplier of 2 until the end of 2033; if their share stays below 1% in 2031, a 2% RFNBO sub-target applies from 2034.

Key dates

• 31 Aug 2024Monitoring plans submitted to verifiers
• 1 Jan 2025First reporting period begins, with a GHG intensity limit at −2% versus the 2020 reference
• 31 Jan 2026First FuelEU reports to verifiers (for 2025)
• 30 Apr 2026Pooling, banking and borrowing decisions for 2025
• 30 Jun 2026First FuelEU Documents of Compliance; penalties for 2025 paid
• 1 Jan 2030Limit tightens to −6%; OPS obligation starts for container and passenger ships in TEN-T core ports

What it means for the fleet office

Every fuel type, its calorific value and its well-to-wake factor matter, and the bunker delivery note provides the evidence. Consistent fuel naming between BDNs, daily reports and the ledger keeps the compliance balance credible and supports informed pooling or banking decisions.

How MATS relates

Applies to

Ships ≥ 5,000 GT on international voyages. IMO DCS applies since 2019 and CII ratings since 2023 for the ship types covered

DCS data

Annual fuel consumption per fuel type, distance travelled and hours underway. Enhanced DCS adds consumption per consumer type, consumption when not underway, onshore power supplied and transport work

Deadlines

DCS report to the flag Administration (or its RO) by 31 March; Statement of Compliance by 31 May

Required CII reduction vs 2019

5% (2023) · 7% (2024) · 9% (2025) · 11% (2026) · 13.625% (2027) · 16.25% (2028) · 18.875% (2029) · 21.5% (2030)

Rating

A to E; a ship rated D for three consecutive years or E for one year must add a corrective action plan to its SEEMP Part III

Review

Phase two of the IMO's CII / SEEMP review is under way, targeted for completion in 2028

How it works

Each ship keeps a data collection plan (SEEMP Part II) and reports its yearly fuel consumption, distance and hours underway to its flag Administration, which verifies the data and issues a Statement of Compliance. The attained CII (CO₂ emitted per capacity-mile) is compared with a required value that decreases every year, and the ship receives a rating from A to E. The rating for a calendar year is confirmed with the Statement of Compliance in the following spring, so the whole year's daily reports decide it.

The enhanced DCS (resolution MEPC.385(81)) adds fuel per consumer type, consumption when not underway, onshore power and transport work. It applies from 2025 or 2026 depending on the flag State's implementation. At MEPC 84 (April–May 2026), further reporting changes were agreed for reporting year 2027: the carbon factor of biofuel blends weighted by mass rather than energy, and distance split between underway and not underway.

The IMO Net-Zero Framework sets a global greenhouse-gas fuel-intensity limit with a two-tier remedial-unit mechanism. It was approved at MEPC 83 in April 2025, but its adoption was adjourned in October 2025. MEPC 84 continued negotiations through intersessional work, and a resumed extraordinary session is scheduled for December 2026 alongside MEPC 85. As of August 2026, the framework is not in force.

Key dates

• 1 Jan 2019IMO DCS data collection begins
• 1 Jan 2023CII rating regime starts; first ratings issued in 2024 for 2023 data
• 2025 / 2026Enhanced DCS data granularity (MEPC.385(81)), depending on flag implementation
• 31 Mar each yearDCS report for the previous year to the Administration or RO
• 31 May each yearStatement of Compliance and CII rating
• 2027 – 2030Required CII reduction factors rise from 13.625% to 21.5%
• Dec 2026Resumed IMO extraordinary session on the Net-Zero Framework, alongside MEPC 85

What it means for the fleet office

CII is decided by the daily reports: hours underway, distance and fuel per type, every day of the year. A wrong noon entry in March can change the rating confirmed the following May. Enhanced DCS also asks for the split by consumer, which the office must be able to reproduce.

How MATS relates