San Diego Signs Fourth Sister Port Deal, This Time With Subic Bay

The Port of San Diego and the Subic Bay Metropolitan Authority of the Philippines signed a sister port Memorandum of Understanding on October 15, formalising a partnership aimed at building two-way trade, exchanging operational knowledge and cooperating on sustainable development. The signing took place during a celebration attended by SBMA dignitaries and local leaders from the Filipino community, and it marks San Diego's fourth sister port agreement in its history.

The deal matters for shippers and forwarders because of what Subic Bay actually is. The Philippine port, located on the west coast of Luzon Island, is a former United States military base repurposed for commercial operations — and its business lines run strikingly parallel to San Diego's. Both organisations run cargo and cruise operations, shipbuilding facilities, foreign trade zones, hotels, marinas, restaurants, wildlife preserves, recreational centres and an airport.

That overlap is the commercial logic behind the MOU. Ports with mirrored asset portfolios can trade operational know-how across every business line rather than limiting cooperation to container throughput alone, and the agreement explicitly covers both port operations and sustainable development.

What does the agreement cover?

According to the port, the partnership will enable the two organisations to:

• Build trade opportunities between the two gateways
• Exchange knowledge on port operations
• Collaborate on shared interests in sustainable development

Commissioner GilAnthony Ungab of the Port of San Diego Board of Port Commissioners framed the MOU as an avenue for deepening ties with the Philippines and collaborating on import and export cargo opportunities in Asia. He also pointed to sharing best practices in three specific areas: sustainable port development, supply chain resilience and environmental stewardship.

For US shippers with Asia-facing supply chains, the language on import and export cargo opportunities signals where any concrete commercial follow-through would land. Subic Bay sits on Luzon's west coast facing the South China Sea, positioning it as an alternative or supplementary Philippine gateway for trans-Pacific freight. No rate, tonnage or capacity commitments form part of the MOU, however — this is a framework agreement, not a service launch.

Who said what at the signing?

Chair Ann Moore of the Port of San Diego Board of Port Commissioners described the partnership as an extension of the port's commitment to innovation through strong international relationships, one that creates opportunities beyond both waterfronts and reinforces economic resiliency.

Moore's emphasis on economic resiliency tracks with Ungab's reference to supply chain resilience, indicating that both commissioners see the relationship as a hedge and a learning channel rather than a purely ceremonial exchange.

How does this fit San Diego's sister port history?

Subic Bay is the fourth sister port relationship the Port of San Diego has established, following agreements with:

• Sasebo, Japan, signed in 1982
• Ensenada, Mexico, signed in 2004
• Nanjing, China, signed in 2012

The cadence — roughly one new agreement every decade to two decades — suggests the port treats these partnerships as long-horizon instruments rather than quick commercial fixes. The gap of 13 years since the Nanjing agreement makes Subic Bay the first new sister port relationship of the modern supply chain disruption era.

What happens next?

Nothing in the MOU itself commits either party to specific volumes, services or timelines. The practical test will be whether knowledge exchange on port operations and sustainable development matures into concrete import-export cargo flows between Southern California and Luzon. Given the shared portfolio spanning cargo, cruise, shipbuilding and foreign trade zones, both authorities have ample ground to convert October 15's signature into operational cooperation.

By James Calloway, Waybill Wire