An Export Control Classification Number looks cryptic — 5A992.c, 3A001.b.3, 0A501 — but every character carries meaning. Once you can read the structure, you can tell at a glance what kind of item an entry covers and why it is controlled.
The five characters
Every ECCN has five characters: a digit, a letter and three digits. Take 3A001:
- 3 — the category: electronics.
- A — the product group: systems, equipment and components.
- 001 — the entry number, whose first digit indicates the main reason for control.
The category digit (0–9)
The first character places the item in one of the ten categories of the Commerce Control List: 0 nuclear and miscellaneous; 1 materials, chemicals, microorganisms and toxins; 2 materials processing; 3 electronics; 4 computers; 5 telecommunications and information security; 6 sensors and lasers; 7 navigation and avionics; 8 marine; 9 aerospace and propulsion. See the ten CCL categories explained.
The product group letter (A–E)
The second character says what kind of thing the item is:
- A — systems, equipment and components
- B — test, inspection and production equipment
- C — materials
- D — software
- E — technology
So 5A002 is encryption equipment, 5D002 is encryption software, and 5E002 is encryption technology. More in CCL product groups A–E.
The three-digit number and what its first digit tells you
The first of the three digits indicates the principal type of control:
- 0xx — national security (for example 3A001, 5A002), largely implementing the Wassenaar Arrangement.
- 1xx — missile technology (for example 7A103, 9A101).
- 2xx — nuclear nonproliferation (for example 2B230).
- 3xx — chemical and biological weapons (for example 1C350, 2B350).
- 5xx — the "500 series", notably 9x515 for spacecraft and related items.
- 6xx — the "600 series": military items moved from the U.S. Munitions List, such as 0A606 or 9A610.
- 9xx — anti-terrorism, crime control and other unilateral reasons (for example 3A992, 5A991, 4A994).
This is a quick guide, not the rule: the License Requirements section of each entry states its actual reasons for control, and many entries carry several (national security and anti-terrorism, for example).
Sub-paragraphs: the part after the dot
Most entries are divided into lettered and numbered paragraphs. The paragraph the item meets is part of its classification:
- 5A992.c — paragraph c of 5A992 (mass-market encryption equipment).
- 5A001.b.5 — paragraph b, sub-paragraph 5 (digitally controlled scanning receivers).
- 6A002.a.1.a — three levels deep: space-qualified solid-state detectors with a given peak response.
The paragraph matters in practice: reasons for control and licence exceptions can differ between paragraphs of the same entry, and your records should show which one the item met.
Special entries worth recognising
- .y paragraphs in 600 series entries (for example 9A610.y) list lower-sensitivity parts controlled mainly for anti-terrorism reasons.
- .z paragraphs (for example 5A992.z) cover items that incorporate advanced computing chips meeting 3A090 or 4A090.
- 0Y521 entries are temporary classifications BIS can create for emerging items.
- EAR99 is not an ECCN — it is the designation for items subject to the EAR that no ECCN describes. See What is EAR99?.
From the code to the licence decision
An ECCN on its own does not tell you whether you need a licence. Its reasons for control are read against the destination on the Commerce Country Chart (Supplement No. 1 to Part 738): an "X" in the matching column means a licence is required unless a licence exception applies. See the Commerce Country Chart explained.
Reading real ECCNs: examples
- 3A001.b.3 — Category 3 (electronics), group A (equipment and components), entry 001 (national security), paragraph b.3: certain microwave components.
- 4A090.a — Category 4 (computers), group A, entry 090: computers containing integrated circuits that meet 3A090.a.
- 7A001.a.1 — Category 7 (navigation and avionics), group A, entry 001: linear accelerometers meeting paragraph a.1.
- 6A003.b.4.b — Category 6 (sensors and lasers), group A: imaging cameras incorporating microbolometer focal plane arrays.
- 2A991.b.2 — Category 2 (materials processing), group A, entry 991 (anti-terrorism): certain bearings for extreme temperatures.
- 9A610.x — Category 9, 600 series: parts and components specially designed for military aircraft.
Why the paragraph belongs in your records
Paragraphs can carry different reasons for control, different licence exception eligibility and different reporting requirements. Customs filings and customer documents often ask for the full ECCN. A record that says only "3A001" cannot show which parameters were compared or which controls applied — and it may be wrong for a variant that falls in a different paragraph.
Common misreadings
- Reading the entry number as a ranking — 5A002 is not "more controlled" than 5A001 because of the number.
- Assuming every 9xx entry is harmless — AT controls still require licences for some destinations.
- Treating EAR99 as a code in the list — it is a designation, not an entry.
See how to read an ECCN entry for the parts of the entry behind the code.
Reading codes in ECCN.help
Every result in ECCN.help shows the full ECCN down to the paragraph, its reasons for control and the rule that decided it — and the licence check reads those reasons against the Country Chart for any destination. Start with an ECCN lookup or classify an item in the ECCN.help Classification Workflow.
ECCN.help provides research and assistance, not legal advice.