What the Numbers Mean in a Federal Tax ID EIN | Bizfluent

What the Numbers Mean in a Federal Tax ID EIN

Written By
Jason Gillikin
Jason Gillikin
May 10, 2010
2 minute read

The Internal Revenue Service (IRS) assigns an employer identification number to every business or non-personal entity (like a club) that requests one. The EIN is to an organization what a Social Security Number is to a person--an official tax identifier used for filing returns and opening banking accounts.

EIN Structure

EINs are nine-digit numbers. Unlike Social Security Numbers, which are in the format 123-45-6789, EINs are in the format 12-3456789. The first two digits had a positional logic, and the remaining six were simply the next numbers in the sequence with no intrinsic meaning.

Prefix Code History

Before 2001, the first two characters of the EIN (called a "prefix code") represented the general geographic area in which a business was expected to operate. After 2001, the code no longer applied in the same way; instead of referring to the business's geographic area, it reflected the location of the IRS office that processed the EIN request.

Prefix Codes

Prefix codes, by assigning city, are as follow: Andover (10, 12), Atlanta (60, 67), Austin (50, 53), Brookhaven (01, 02, 03, 04, 05, 06, 11, 13, 14, 16, 21, 22, 23, 25, 34, 51, 52, 54, 55, 56, 57, 58, 59, 65), Cincinnati (30, 32, 35, 36, 37, 38, 61), Fresno (15, 24), Kansas City (40, 44), Memphis (94, 95), Ogden (80, 90), Philadelphia (33, 39, 41, 42, 43, 45, 46, 47, 48, 62, 63, 64, 66, 68, 71, 72, 73, 74, 75, 76, 77, 81, 82, 83, 84, 85, 86, 87, 88, 91, 92, 93, 98, 99), Internet (20, 26, 27), Small Business Administration (31).

Advertisement

Remaining Digits

The final six digits of an EIN have no significance whatsoever--they are assigned in sequence with no special positional logic. However, two new EINs may not be issued with consecutive numbers.

Recycling EINs

When a company or organization dissolves, the EIN is deactivated. It is possible that an EIN may be re-used at a future date, although the statistical incidence of this happening is fairly small.

Jason Gillikin

Jason Gillikin is a copy editor and writer who specializes in health care, finance and consumer technology. His various degrees in the liberal arts have helped him craft narratives within corporate white papers, novellas and even…

Bizfluent Logo

Bizfluent equips entrepreneurs with the tools and tactics they need to build and grow their small businesses, from starting a first venture to refreshing an established one.

Property of TechnologyAdvice. © 2026 TechnologyAdvice. All Rights Reserved

Advertiser Disclosure: Some of the products that appear on this site are from companies from which TechnologyAdvice receives compensation. This compensation may impact how and where products appear on this site including, for example, the order in which they appear. TechnologyAdvice does not include all companies or all types of products available in the marketplace.