US Maritime Administration

The US Maritime Administration (MARAD) is an agency within the US Department of Transportation responsible for the vitality of the US maritime industry. Its most operationally significant function in conflict contexts is the issuance of Maritime Advisories, formal notices alerting commercial shipping to specific threats in defined geographic areas. These advisories — used alongside UK Maritime Trade Operations (UKMTO) alerts — are the primary official channel through which the Shipping Industry receives threat intelligence, enabling masters and operators to make routing and risk decisions.

Since the outbreak of the 2026 Iran-Israel war, MARAD has issued multiple advisories covering the Strait of Hormuz, Gulf of Oman, and Red Sea. Advisory 2026-004 confirmed severe GNSS/GPS interference spanning from Hormuz to Bab al-Mandeb, characterising it as a deliberate electronic denial zone affecting two of the world's three critical maritime chokepoints. Earlier advisories flagged armed unmanned surface vessels (drone boats) following Iran's first direct deployment of explosive USVs.

MARAD advisories carry no mandatory compliance requirement but have significant commercial weight: war-risk insurers use them as reference points when pricing hull and cargo premiums, and many corporate shipping policies require compliance with MARAD and UKMTO guidance. A MARAD advisory covering a major transit route can effectively redirect billions of dollars of daily shipping traffic with no legal coercion required.