The crude oil tanker IMO 9412359 sits on the US and UK lists under two different names. OFAC lists it as NS BRAVO, flagged in Gabon and linked to Sovcomflot, while the UK Sanctions List specified it on 25 November 2024 as BELGOROD, flagged in Russia. Neither entry carries the other's name as an alias. A search for 9412359 finds both.
Either entry can change after the day you check, so the vessel check belongs in ongoing client screening that rescreens a counterparty after onboarding.
What is a sanctioned vessel?
A sanctioned vessel is a ship that a sanctions authority has listed by name and IMO number, or a ship that belongs to someone whose property is blocked.
OFAC's Specially Designated Nationals list treats a listed ship as blocked property: 1,568 vessel entries on 28 October 2026, 672 under Iran programs and 444 under Russia programs. The UK specifies ships. A specified ship is barred from UK ports, and the UK list held 683 of them on 30 October 2026. The EU bans listed ships from its ports and from receiving services, and its 21st package of 23 July 2026 added 41 vessels "on top of the 632 already sanctioned". The UN Security Council listed the tanker AVAX (IMO 9058713) on 22 July 2026.
In the UK and the EU, most listings are Russia related. The UK specified 110 ships in 2024, 432 in 2025 and 104 in 2026 up to 30 October, and 645 of its 683 sit under its Russia regulations. The European Commission counts the EU's 632 as "Russia's shadow fleet", listed to cut Russian oil revenue.
A ship with no entry of its own can still be blocked through its owner. Under OFAC's 50 Percent Rule, if one or more blocked persons own the owning company 50 percent or more, counting direct and indirect stakes, that company's property is blocked, and the ship is part of it. So the vessel check runs up the owner chain to the ultimate beneficial owner.
Why does the IMO number matter more than the ship's name?
A ship keeps its IMO number for life. The International Maritime Organization started the scheme in 1987 under resolution A.600(15) and made it mandatory from 1 January 1996 for passenger ships of 100 gross tonnage and up and cargo ships of 300 and up. The number stays the same when the ship moves to another flag and, in the IMO's words, "is never reassigned to another ship".
Names and flags do change. Of the 1,568 vessel entries on OFAC's file, 1,551 carry an IMO number, and OFAC's alias file gives 145 of them 212 other names, 99 marked as former names. A name search tests those names one at a time, while the IMO number reaches the hull behind all of them. The IMO also numbers the companies and registered owners that manage ships on international voyages, and that number helps when you screen the owner.
How do you spot a mistyped IMO number?
The seventh digit is a check digit. Multiply the first six digits by 7, 6, 5, 4, 3 and 2 and add the results; the last digit of the sum must equal the seventh digit. For 9412359 that is 63 + 24 + 5 + 8 + 9 + 10 = 119, and the check digit is 9. All 1,551 IMO numbers on OFAC's file pass this test. Treat a number that fails it as a typo and go back to the ship's papers.
Where can you check if a vessel is sanctioned?
Table 1. Where ships are listed, counted from the official files on 1 November 2026
| List | Publisher | How a ship appears | Ships listed | What the listing stops | Where to search |
|---|---|---|---|---|---|
| OFAC SDN | US Treasury | name, IMO number, flag, type, linked owner or operator | 1,568 entries (list of 28 October 2026) | any dealing by a US person; the ship is blocked property | Sanctions List Search, type Vessel |
| UK Sanctions List | FCDO, for every UK regime | name, IMO number, current and previous owners and flags | 683 ships (30 October 2026) | UK port access and UK registration | gov.uk list page, CSV, ODS or XML file |
| EU Annex XLII, Regulation 833/2014 | Council of the EU | name with former name where known, IMO number, ground, date | 632 after 23 April 2026, then 41 more on 23 July 2026 | EU port access and services to the ship | Official Journal amending acts |
| UN Consolidated List | Security Council committees | name, with the IMO number in the entry's notes | AVAX, listed 22 July 2026 under the Libya measures | loading, carrying or discharging petroleum, port entry, bunkering | UN Consolidated List |
On OFAC's Sanctions List Search, set Type to Vessel and enter the IMO number in the ID field. A name search on the same page scores each result against a Minimum Name Score setting, so near names appear beside exact ones. The UK publishes one list. It comes as CSV, ODS and XML files, with columns for the IMO number, the owners and the flags. The separate OFSI Consolidated List closed on 28 January 2026, so the UK Sanctions List is now the only UK source.
The EU prints its vessel annex in the Official Journal, one amending act per package. Regulation (EU) 2025/2033 of 23 October 2025 added entries 448 to 562, such as "GELOR (formerly ARTARA)".
Four searches by hand mean four sites and four formats. The free vessel sanctions check from complead, formerly Sanction Scanner, takes an IMO number or a name and searches current and former names across the OFAC, State Department, UK, EU and UN vessel listings. It shows the listings on screen and emails a PDF with the program, listing date, former names and linked owners. The on screen check needs no account.
What does a full vessel check cover beyond the list?
A list check tells you whether the hull is listed. The May 2020 maritime advisory from OFAC, the State Department and the US Coast Guard names seven deceptive shipping practices, and most of them leave no trace on a list. Five checks cover them.
- Owner, manager and operator. The advisory warns of shell companies and repeated changes of owner or manager. Screen each company by name with a free sanctions check, and use an LEI lookup to confirm its legal name and parent.
- Flag history. Frequent flag changes in a short period, called flag hopping, and a flag kept after deregistration are both red flags in the advisory. The UK list records previous flags for 50 of its 683 ships.
- AIS record. Look for gaps in the ship's Automatic Identification System signal and for spoofing, where a ship broadcasts another name or IMO number to hide its movements.
- Ship to ship transfers. Cargo moved between ships at sea, especially at night or in high risk areas, can hide where it came from or where it is going. Before a transfer, the advisory suggests checking the other ship's name, IMO number and flag.
- Documents and route. Compare the bill of lading, the certificate of origin and the route with the cargo. Falsified papers and unexplained detours point to trade based money laundering as well as sanctions evasion.
These checks feed the same decision as the list check. Picture a ship that sits on no list, changed owner last month and went dark on AIS for ten days near a transfer area. An analyst reviews it first.
Can vessel identity laundering beat an IMO search?
It can, when the listed ship borrows the real IMO number of another hull. Vessel identity laundering dresses a listed ship in a false identity so that it can keep trading. The 2020 advisory describes ships that "painted over vessel names and IMO numbers", and AIS spoofing broadcasts another ship's name or number. A borrowed number is a valid number, so it passes the check digit.
The IMO scheme still exposes it. A number is never reassigned, so two ships under one number, or a number whose recorded type, size or build year does not match the ship in front of you, is the signal to stop and ask.
Is a vessel hit a match on the hull or only on the name?
Read a result by the identifier it matched on. A match on the IMO number is a match on the hull: treat the ship as listed until an analyst shows otherwise. A match on the name alone is a lead and often a false positive, because two ships can share a name.
Picture a bill of lading that names a bulk carrier sharing its name with a listed tanker, with a different IMO number, ship type and build year. The analyst records a name match, clears it and writes down why.
For a real hit, read four fields: the list and its program, the listing date, the other names, and the linked owner or operator. OFAC links 1,542 of its 1,568 vessel entries to an owner or operator, and that company goes through screening next. A clean result covers the ship only. The owner, the cargo and the ports on the route need their own checks.
How often do the vessel lists change?
Every few days, though not every change touches a ship. The UK Sanctions List changed on 26, 27, 29 and 30 October 2026, and OFAC last updated the SDN list on 28 October 2026. A ship cleared last month can be listed this week, so rescreen the ship and its owners for as long as the deal is open.
What happens to the deal when the ship is listed?
A confirmed hit stops the deal. Work through four steps in this order.
- Stop. Do not finance, insure, charter or pay for the ship, its voyage or its cargo until compliance clears it. For a freight or charter payment, payment screening reads the whole message, so a designated vessel named in the reference field can be caught even when the sender and the receiver are clean.
- Block or reject, then report. Under 31 CFR 501.603, a US person files a blocked property report with OFAC within 10 business days of the blocking. Other regimes set their own reporting duties.
- Report the suspicion. The 2020 advisory reminds US financial institutions of their duty to file a suspicious activity report when a transaction has no business or apparent lawful purpose.
- Keep the record. Save the search, the result, the list entry and who decided, including the searches that found nothing.
Three changes to make before the next charter or cargo file comes in:
- Add an IMO number field to every trade, charter and insurance file that names a ship, and search by it.
- Rescreen the owners and managers of the ships you already finance or insure.
- Ask whoever runs your screening which of the four lists it covers and whether it searches former names.
How this page was checked. Sinan Tekin wrote this guide and Ufuk Gürdaş, Compliance Specialist, reviewed it. The counts come from the official files read on 1 November 2026: OFAC's SDN and alias files (updated 28 October 2026), the UK Sanctions List CSV (30 October 2026) and the UN Consolidated List (31 October 2026). The check digit test ran on all 1,551 IMO numbers in OFAC's file. EU figures come from the Commission's package notes and Regulation (EU) 2025/2033.
