A DEA number (DEA Registration Number) is an identifier assigned to a health care provider (such as a physician, physician assistant, nurse practitioner, optometrist, dentist, or veterinarian) by the United States Drug Enforcement Administration allowing them to write prescriptions for controlled substances.
Though there is no legal basis for preventing its use as a general prescriber identification number, for security reasons the DEA prefers that DEA registration numbers only be used for authenticating and tracking prescriptions for controlled substances. The agency prefers that the National Provider Identifier be used for general identification purposes.
A valid DEA number consists of:
- 2 letters, 6 numbers, and 1 check digit
- The first letter is a code identifying the type of registrant (see below)
- The second letter is the first letter of the registrant's last name, or "9" for registrants using a business address instead of name.
- Of the seven digits that follow, the seventh digit is a "checksum" that is calculated similarly to the Luhn algorithm, with the following steps:
- Add together the first, third and fifth digits call this CALC1,3,5
- Add together the second, fourth and sixth digits and multiply the sum by 2, call this CALC2,4,6
- Add CALC1,3,5 + CALC2,4,6 call this CHECK
- The rightmost digit of CHECK (the digit in the ones place) is used as the check digit in the DEA number
Registrant type (first letter of DEA Number):
- A/B/F/G – Hospital/Clinic/Practitioner/Teaching Institution/Pharmacy
- M – Mid-Level Practitioner (NP/PA/OD/ET, etc.)
- P/R – Manufacturer/Distributor/Researcher/Analytical Lab/Importer/Exporter/Reverse Distributor/Narcotic Treatment Program
For example, for a registrant using a business address instead of a name, the DEA number might look like "F91234563". In some cases, multiple people (possibly including interns or nurses) are prescribing under the supervision of a more senior prescriber. In this case, the supervised individual may be identified by affixing an ID string to the end of the supervisor's DEA number, after a dash, e.g. "F91234563-001AB".
Prior to October 1, 1985, DEA registration numbers for physicians, dentists, veterinarians, and other practitioners started with the letter A. New registration numbers issued to practitioners after that date begin with the letter B, F, or G.  The rest of the format was the same as the new style.
- "Miscellaneous Questions / Security". Retrieved 9 Feb 2017.
- "DEA Numbers Definition and Construction". August 27, 2008. Archived from the original on 2016-12-21.
- "Pharmacist's Manual - SECTION IX-XIV: Section IX – Valid Prescription Requirements". U.S. Department of Justice: Diversion Control Division. Retrieved June 26, 2019.
- http://www.deadiversion.usdoj.gov/drugreg/reg_apps/new_reg_number110906.html[dead link] "Due to the large Type A (Practitioner) registrant population, the initial alpha letter "B" has been exhausted. DEA will begin using the new alpha letter "F" as the initial character for all new registration for Type A (Practitioner) registrations."