The SDN list is OFAC's primary list of individuals, entities, vessels, and increasingly crypto addresses whose property is blocked and with whom US persons are generally barred from dealing. It is the central reference for US blocking, and its reach extends through the 50 Percent Rule to unnamed entities that SDNs own.
What is the SDN list, in plain English?
The SDN list, short for Specially Designated Nationals and Blocked Persons list, is the main US sanctions list. It is maintained by OFAC, the Treasury office that runs US sanctions, and it names the individuals, companies, vessels, and now crypto wallet addresses whose property is blocked. US persons are generally prohibited from dealing with anyone on it, and their assets that touch the US financial system must be frozen.
It is the central reference for US blocking. When a payment or a customer matches an SDN entry, the default action is to block the property and report it, not merely decline the business. The list carries far more than names: aliases, dates of birth, addresses, passport and vessel identifiers, and program codes that say which sanctions authority applies.
Its reach goes past the names printed on it. Through the 50 Percent Rule, any entity owned 50 percent or more, directly or indirectly, by one or more SDNs is itself treated as blocked even though it is not listed. That is why screening the SDN list alone, without ownership analysis, leaves a hole.
How screening against the SDN list works
- Ingest — Pull the current list. Load OFAC's latest SDN data, including aliases and secondary identifiers, since OFAC updates it frequently.
- Match — Apply fuzzy and phonetic logic. Compare names with fuzzy, phonetic, and transliteration matching so spelling variants are caught.
- Enrich — Check ownership. Test whether an unlisted counterparty is owned by SDNs under the 50 Percent Rule.
- Act — Block and report. On a confirmed match, block the property and file the blocking report with OFAC.
What ends up on the list?
Entry type | What it covers |
Individuals | Named people with aliases, dates of birth, and passport or ID numbers. |
Entities | Companies and organizations, plus the unnamed entities they own via the 50 Percent Rule. |
Vessels | Ships identified by name and IMO number tied to sanctioned activity. |
Crypto addresses | Digital currency wallet addresses linked to designated parties, an area OFAC has expanded. |
What it looks like in practice
In practice
An institution runs its payment screening against a copy of the SDN list that was refreshed three weeks ago. A beneficiary added by OFAC last week clears, because the party simply is not in the stale file. The payment settles, and the institution has processed a blocked party without knowing it.
A second gap shows up separately. A counterparty whose name is not on the list is owned by a listed individual. Exact, name-only matching finds nothing, but ownership enrichment flags the 50 Percent Rule and the analyst blocks the funds. The two near-misses push the team to automate daily list refreshes and add ownership screening on top of name matching.
Why it matters for operators
The SDN list is the backbone of US sanctions compliance, and OFAC enforces breaches on a strict-liability basis. Processing a payment for an SDN, even unknowingly, can be a violation, so the list is not a reference you consult occasionally; it is a control you have to keep current and match against carefully every time.
The failure mode is predictable: exact-match, name-only screening on a stale copy. That combination misses spelling and transliteration variants, misses entities owned but not named under the 50 Percent Rule, and misses anyone added since the last refresh. Each of those gaps has let real blocked parties through, which is why fuzzy matching, ownership analysis, and frequent updates are treated as baseline rather than nice-to-have.
What to watch in the data
- Stale copies. OFAC updates the SDN list frequently; screening against an old file misses recently designated parties.
- Exact-match only. Without fuzzy, phonetic, and transliteration logic, spelling variants of a listed name slip through.
- Missing aliases. SDN entries carry many aliases and secondary identifiers; ignoring them narrows your coverage.
- Ownership gaps. Entities owned but not named are still blocked under the 50 Percent Rule and need ownership screening.
- New entry types. Vessels and crypto addresses are on the list too; screening only person and company names misses them.
Quick questions
Who maintains the SDN list?
OFAC, the Office of Foreign Assets Control within the US Treasury. It designates parties, publishes the list, and updates it frequently, sometimes multiple times a week, so screening copies have to stay current.
What happens when I match an SDN?
The default action is to block the property, meaning freeze it so no one can move it, and report the block to OFAC. This is different from rejection, where funds are returned rather than held.
Does the SDN list cover parties that are not named on it?
Yes, indirectly. Under the 50 Percent Rule, an entity owned 50 percent or more by one or more SDNs is treated as blocked even though it is not listed. Name-only screening misses these owned-but-unnamed entities.
Are crypto addresses really on the SDN list?
Yes. OFAC has increasingly added digital currency wallet addresses tied to designated parties. Screening programs that handle crypto need to match against these addresses, not just names.
Why is exact-match screening a problem?
Because sanctioned names are often transliterated from other scripts and carry many spellings and aliases. Exact matching on a single spelling misses valid variants, so fuzzy, phonetic, and transliteration matching are needed to catch the same party under a different rendering.
Go deeper
- OFAC, US Treasury ↗ — Administers US sanctions programs, the SDN list, and licensing.
- European Banking Authority ↗ — EU banking regulator. Strong Customer Authentication under PSD2 and AML guidance.