April 2025 Iran Tanker Tracker

On April 16, 2025, the U.S. Department of the Treasury’s Office of Foreign Assets Control (OFAC) issued a significant update to its maritime sanctions advisory aimed at helping global shipping and trade stakeholders detect and prevent the evasion of U.S. sanctions on Iranian oil.

This latest advisory reflects a growing urgency. It marks the first such update under President Trump's renewed "maximum pressure" campaign against Iran, formally reinstated in February 2025 through National Security Presidential Memorandum-2 (NSPM-2). The goal is clear: drive Iran’s oil exports — and, by extension, its destabilizing activities — down to zero.

As Iran’s maritime smuggling tactics have grown more sophisticated, OFAC has responded by expanding its guidance, adding critical new warnings and real-world examples. This new advisory should be seen as both a wake-up call and a roadmap for compliance in an increasingly high-risk environment for the shipping industry, energy traders, insurers, and financial institutions.

Among the most important new elements:

• For the first time, OFAC estimates that Iran is exporting around 1.6 million barrels per day of crude oil and 0.4 million barrels per day of refined petroleum products despite heavy sanctions. Iran’s key export hubs — Kharg Island, Bandar Mahshahr, and Bandar Abbas — are highlighted, making it clear where much of the illicit traffic originates.
• In a new warning, OFAC points to a separate fleet of older gas carriers that exports liquefied petroleum gas (LPG), particularly to China. While Iran’s oil tankers have long been under scrutiny, this new advisory recognizes that LPG shipments now pose similar sanctions and safety risks.
• The advisory goes further than before in calling out certain jurisdictions that enable Iran’s shadow fleet. Ports and authorities that disregard substandard ships, allow bunkering and services for sanctioned vessels, or fail to enforce international maritime regulations are now firmly in OFAC’s sights.

OFAC’s April 2025 advisory also highlights several emerging tactics Iran is using to move its oil and evade detection:

• Shadow fleet vessels increasingly falsely claim registration under flags of convenience, pretending to be registered with states they have no legal ties to.
  Maritime stakeholders are urged to check vessel registrations carefully — including consulting the IMO’s GISIS database — to avoid facilitating Iranian oil trades unknowingly.
• Iranian tankers are not just conducting isolated STS transfers. According to OFAC, it is now common for Iranian-origin oil to be moved three to five times between vessels — often at night, in poorly monitored waters like the South China Sea or near Indonesia — to thoroughly obscure the origin of the cargo. For example, OFAC documents transfers near Nipa, Indonesia, and Singapore’s Eastern Outer Port Limits, where sanctioned Iranian tankers have used successive swaps to hide the cargo’s provenance before delivering it to third-country buyers.
• Iranian-linked networks increasingly falsify bills of lading, certificates of origin, and insurance papers to conceal Iranian oil's true origins. This paperwork fraud often exploits jurisdictions with lax oversight or uses corrupt or complicit officials to generate seemingly legitimate documentation.

Why It Matters

The stakes are high. Iran’s oil revenues fund the Islamic Revolutionary Guard Corps (IRGC), terror proxies like Hezbollah, and missile proliferation programs across the Middle East.

Without robust enforcement — and without private sector vigilance — Iran’s shadow fleet will continue to prop up a regime dedicated to destabilizing U.S. allies and partners.

This advisory makes it clear:

• Maritime stakeholders must go beyond surface-level due diligence.
  Vessel ownership, insurance legitimacy, flagging history, voyage patterns, and cargo documentation must all be scrutinized.
• Ports, insurers, and brokers must refuse services to suspicious vessels.
  Turning a blind eye is no longer a viable defense against sanctions risk.
• Industry information-sharing and collaboration are essential.
  OFAC is encouraging real-time benchmarking and intelligence sharing between companies to catch evasion patterns early.

Despite these efforts, Iran’s oil exports to China continued through April 2025, sustaining a critical revenue lifeline for the regime.

*figures to be updated over the following weeks.

Ship-to-ship (STS) transfers — many involving sanctioned vessels — persisted off the coasts of Singapore and Malaysia, particularly in loosely monitored waters near the Riau Islands and the Eastern Outer Port Limits. While the United States has stepped up enforcement actions, Iran has adapted by finding new ways to move oil more discreetly.

This month's notable trend was the increasing use of vessels previously implicated in Russian sanctions evasion. Several tankers originally involved in facilitating Russian oil trades after the imposition of Western price caps have now shifted to carrying Iranian-origin cargo.

This blending of Iranian and Russian sanctions evasion networks is significant. It suggests:

• Shared facilitators and infrastructure: Brokers, insurers, crewing companies, and flag registries that once specialized in Russian cargo are now servicing Iranian oil trades.
• Excess supply of risky vessels: As enforcement against Russian oil shipments has intensified, vessels that once operated in Russia’s shadow fleet may have shifted focus to Iran — an equally lucrative opportunity.
• Greater difficulty for sanctions enforcement: Ships with prior Russian exposure may already operate with falsified documents, disguised ownership, and experienced crews adept at evasion, making them harder to track and interdict when switching to Iranian cargos.

Iran’s maritime sanctions evasion tactics have reached new levels of complexity.
The April 2025 OFAC advisory reflects a much-needed recognition that the risk landscape has shifted:

• The dark fleet is growing, now augmented by vessels formerly tied to Russian sanctions evasion.
• Deceptive practices are more entrenched, with multilayered STS transfers, document falsifications, and fraudulent flagging.
• Maritime stakeholders are being called on to actively stop these trades — not just through basic compliance but through rigorous due diligence, contract enforcement, and active refusal of suspicious transactions.

As the Iranian regime finds new ways to fund its destabilizing activities, UANI will continue to track, expose, and confront the evolving threats posed by Iran’s maritime network.

The shipping industry, financial institutions, insurers, and port authorities must remain vigilant.
The stakes — for regional stability, global security, and enforcement of international norms — have never been higher.