Mediterranean
0.10% sulfur ECA.

The Mediterranean 0.10% sulfur ECA — the entry-into-force trigger under the IMO amendment cycle, the three compliance routes an operator can take on a per-voyage basis, and the vessel types and Mediterranean voyages that fall in scope for ships calling Med ports. Direct line: hello@astrabemarine.com.

Open a Med ECA engagement See the trigger mechanic

Direct line — partner-led, not delegated

hello@astrabemarine.com

Where this fits

A reference page for the 0.10% sulfur Med regime — not a replacement for counsel.

The Med ECA sits inside Astrabe’s broader regulatory-compliance mandate, beside the EU ETS phase-in, CII & EEXI, IHM, CSRD / ESG. The page is the working reference for the entry-into-force mechanic, the three operator compliance routes, and the vessel and voyage surface area that determines a ship’s exposure on any given Med call.

Compliance mandate

Full regulatory-clock mandate, end-to-end

See the home page practice areas.

Med ECA detail

Trigger mechanic, three compliance routes, scope

You are here.

Entry-into-force trigger

How the amendment becomes binding — MEPC, deemed acceptance, and the tonnage threshold.

The Med ECA does not enter into force on a fixed calendar date. It locks in once the IMO MARPOL Annex VI amendment reaches a ratification threshold calibrated to world tonnage. The mechanic is a three-step cycle — MEPC adoption, then a 12-month deemed acceptance window, then a tonnage-count test — and the operator consequence (a 0.10% S or equivalent compliance obligation) runs from the date the threshold is met.

Step 01

MEPC

MEPC adoption of the MARPOL Annex VI amendment.

The Marine Environment Protection Committee adopts the designated amendment to MARPOL Annex VI introducing a Mediterranean 0.10% sulfur emission control area. Adoption sets the clock for the next step — the rule is now in international pipeline, not yet in force.

Step 02

12 mo

12-month deemed acceptance window.

Once adopted, the amendment is open for explicit acceptance. Where no State raises an objection within the prescribed period, the amendment is deemed accepted by all Parties. The 12-month window is the moderation phase — the period during which the operative date is contested or confirmed.

Step 03

>50%

Tonnage-based ratification threshold (>50% of world tonnage).

Entry into force is triggered when the accepting States together account for more than fifty percent of the world’s gross tonnage of merchant shipping. Once met, the amendment enters into force and the 0.10% sulfur cap binds the in-scope fleet on Med operations.

Compliance routes

Three compliance routes. The fuel route, the scrubber route, and the equivalent route.

Once the regime binds, an operator’s compliance is satisfied through any of three routes that MARPOL Annex VI recognises as equivalent. The three routes sit on the same legal footing — operators are free to combine them across a fleet, but each vessel must be able to evidence which route covers each voyage.

Fuel route
VLSFO 0.10% S / MGO on board.
Use a compliant fuel oil — very-low-sulfur fuel oil at 0.10% sulfur or marine gasoil / diesel — from bunker purchase onward. The Bunker Delivery Note is the documentary chain a port-state inspection or audit will read first; fuel switching, sampling, and tank segregation must be tight enough to defend the source.
Scrubber route
EGCS — equivalent SOx wash-down.
Operate an approved Exhaust Gas Cleaning System (scrubber / EGCS) running on HSFO, with the wash-down reducing stack SOx to the equivalent of a 0.10% sulfur fuel. The retrofit is documented per vessel, the operating ratio is auditable, and the BDN corresponds to HSFO — the equivalence sits in the unit, not the bunker.
ACE route
Alternative compliance equivalent — case-by-case approval.
Where a vessel cannot run the fuel route or the scrubber route, an Alternative Compliance Equivalent (ACE) may be recognised where the Administration accepts the emission outcome as equivalent. This is a per-case route — bunker purchasing teams should not assume it is available without first securing Administration sign-off.

Vessel & voyage scope

Which vessels are in scope, and which voyages count as Mediterranean.

The Med ECA captures most commercial vessel types calling Mediterranean ports, with explicit exclusions for yacht and recreational tonnage and for non-propelled craft. The voyage test is also tighter than the EU ETS — a Mediterranean port-to-port voyage is fully in scope, including the at-berth leg, while transit legs through the Med retain separate treatment.

Coverage

All propulsion types · full Mediterranean trade

The Med ECA does not gate on a tonnage threshold in the way the EU ETS does; the operative boundaries are propulsion type and Med-trade exposure rather than vessel size. Yacht and non-propelled craft are excluded by category, not by size.

Vessel type

Cargo vessels (general / bulk)
General cargo and dry bulk carriers are in scope at all tonnage tiers covered by MARPOL Annex VI. The 0.10% sulfur cap governs the at-sea leg into, between, and out of Med ports and binds the bunker purchasing team to a compliant fuel slate or scrubber operating regime.
Tankers (oil, chemical, product)
Oil, chemical, and product tankers are in scope. Tanker Med trades touch both intra-Med port-to-port voyages and Med transit legs — the difference between the two voyage categories matters for the documentary chain on each call.
Passenger vessels (ferries, cruise)
Passenger ships calling Mediterranean ports — including ro-pax ferry operations and cruise itineraries — are fully in scope. The at-berth leg sits within the 0.10% sulfur cap, with port reception and shore-power rules layered on top.
Container vessels
Container ships on Med trade are in scope at the cadence of any container rotation that includes a Mediterranean call. Bunker procurement on the rotation is read against the 0.10% S requirement, and fuel-switch over points matter when the rotation spans an ECA / non-ECA boundary.
Excluded — yacht & recreational craft
Yachts and recreational vessels are not captured by the Med ECA on the same footing as commercial tonnage. They retain their own advisory track with Astrabe and are not part of the 0.10% sulfur compliance obligation on a Mediterranean call.
Excluded — non-propelled craft
Non-propelled craft and platforms are outside the regime. The propulsion test is the entry condition; barges and similar non-self-propelled units alone do not trigger the obligation, even on a Mediterranean port call.

Voyage type

Med port-to-port
Mediterranean port-to-port voyages.
Voyages between two Mediterranean ports — fully in scope under the regime. The 0.10% S cap applies on the at-sea leg, a separate at-berth layer applies alongside, and the documentary chain on the bunker purchase is the first line of defence in any port-state check.
Med at-berth
At-berth legs in Med ports.
The at-berth leg counts separately from the at-sea leg and sits within the 0.10% sulfur bound. Where a Med port provides shore-power or has a specific auxiliary boiler regime, the compliance route chosen on board must be reconciled with the port-side supply.
Med transit
Med transit legs.
Transit legs through the Mediterranean — calling at a Med port as part of a longer voyage — are in scope for the at-sea leg between the Med entry and exit. The bunker slate for the Med transit is read against the 0.10% S requirement and must be auditable alongside the BDN.

Open the conversation

Tell us the vessel, the Med trades, and the bunker slate. We respond within one working day.

Same direct-line model as the broader compliance mandate — no intake form, no sales qualification. Our team takes the first reply and routes the matter to the named counsel; the scoping call runs once the counsel is on the file.