Spain Introduces Marine Fuel Supplier Decarbonisation Mandate as Rotterdam Sales Fall

Spain has introduced a new regulatory framework requiring marine fuel suppliers to reduce the greenhouse gas (GHG) intensity of fuels supplied to domestic shipping, making it the second EU country after the Netherlands to place the decarbonisation obligation primarily on fuel suppliers rather than individual vessels.

Royal Decree 611/2026, published on July 23, 2026, establishes a phased GHG-intensity reduction trajectory for suppliers serving domestic cabotage shipping. The requirement begins with a 6.5% reduction in 2027 and increases to 33% by 2040.

A separate renewable fuel target will rise from 2% in 2027 to 20% by 2040. Renewable fuels of non-biological origin (RFNBOs) can contribute towards the targets if they satisfy applicable sustainability criteria and deliver at least 70% lifecycle GHG savings against the relevant fossil-fuel comparator.

Fuel Suppliers Face New Compliance Requirements

The Spanish rules apply primarily to fuel suppliers, including petroleum and LPG companies, natural gas marketers and certain direct consumers. The obligations are therefore structured around the fuel supply chain rather than being imposed directly on individual vessels.

The decree also establishes requirements covering certification, fuel traceability and reporting. Supporting documentation generally must be retained for a minimum of five years.

The regulatory approach follows the Netherlands, which introduced similar requirements as part of its transposition of the EU Renewable Energy Directive III (RED III). The Dutch rules entered into force on January 1, 2026, requiring suppliers to reduce the GHG intensity of bunker fuels sold in the country.

Rotterdam Bunker Sales Decline After Dutch Rules

The Netherlands’ experience has become a reference point in discussions about the potential market effects of national fuel-supplier mandates.

Rotterdam’s conventional bunker sales fell to 1.58 million tonnes during the first quarter of 2026, according to data cited by PortXchange. The volume represented a 28.1% year-on-year decline and a 27.2% reduction from the previous quarter, making it the port’s lowest quarterly total since at least 2010.

When biofuel blends were included, total bunker sales stood at 1.69 million tonnes, down 26.8% year on year.

PortXchange Managing Director and Co-Founder Sjoerd de Jager said the Netherlands “played it straight,” while Belgium delayed and Germany chose not to introduce equivalent requirements. He said the movement of bunker volumes between neighbouring ports demonstrated the potential impact of differing national regulatory requirements, adding that Spain was now introducing a similar framework.

Regulatory Fragmentation Raises Port Competition Questions

The Spanish policy has renewed discussion about how national fuel-supplier requirements could affect bunker markets in a sector where vessels can source fuel from competing ports in different jurisdictions.

PortXchange has pointed to the shift in bunker volumes around Rotterdam and Antwerp as an example of how differences in national requirements can influence where fuel is purchased. The development also highlights a broader question about whether national measures can deliver consistent decarbonisation outcomes when neighbouring markets operate under different rules.

The issue is emerging as the International Maritime Organization (IMO) continues work on its global Net-Zero Framework. Differences between national and international requirements could create additional compliance considerations for shipowners and fuel suppliers operating across multiple jurisdictions.

Spain’s Rules and FuelEU Maritime

Spain’s supplier-focused approach operates alongside FuelEU Maritime, the EU-wide regulation governing the GHG intensity of energy used by ships.

FuelEU Maritime requires the GHG intensity of energy used by ships to decline progressively, starting with a 2% reduction in 2025 and reaching an 80% reduction by 2050. The regulation also contains provisions supporting the uptake of RFNBOs and requires certain passenger and container ships to use shore-side electricity at major EU ports from 2030.

The coexistence of EU-wide requirements with national fuel-supplier mandates means shipping companies and bunker suppliers may need to manage different regulatory mechanisms depending on where fuel is supplied.