Essential Sources: NAICS and SIC Manuals

This installment of the Essential Sources series focuses on two indispensable resources for business research, the SIC and NAICS manuals. Both manuals are industrial classification systems, meaning that they attempt to organize and assign a code number to every conceivable industry that exists. Not just an exercise in cataloging, these manuals are an essential guidebook when doing any kind of business research. Let’s find out why!

We’ll start with the one most people are probably familiar with, the Standard Industrial Classification Manual, often referred to simply as the SIC manual. The classification system used in the SIC manual dates from the late 1930’s and was periodically updated, with the most recent changes made in 1987. The manual was produced by the United States Office of Management and Budget. The purpose of the manual is to define the standards by which the U.S. government classifies an industry for statistical studies. Any statistics which are produced by the federal government regarding a particular industry, say, all
establishments which make metal doors, are able to be correctly located and compared over time using the code 3442. Although the federal government creates a lot of statistics, SIC codes have been even more widely used as a commonly understood identifier for an industry in most commonly used business research books. The codes can be used in many different ways: to locate lists of companies to contact regarding procurement opportunities, to keep tabs on competitors, and to search for trade associations for a particular industry. The SIC code is so useful, in fact, that the U.S. outgrew the code and has developed a new, more detailed system.

The North American Industry Classification System, or NACIS (pronounced “nakes”) is the replacement for the SIC system. Developed jointly by the governments of Canada, Mexico, and the United States, the NACIS code is everything that the SIC code was, but it is also provides the three countries with a common system for industrial classification which allows researchers to compare international statistical data more accurately. NACIS also provides a more detailed breakdown of each industry, separating out some industries which had been lumped together in the old system, and creating new classification categories for industries that did not existed in the 1987 SIC manual, such as computer disaster recovery services. Since NACIS was introduced a few years ago, more and more research sources are switching over to using this system. Using NACIS might help some businesses locate new statistical data that was previously obscured under a broader SIC code, so even old hands at SIC should take the plunge and switch to NACIS.

Want to see NACIS and SIC codes in action? Head over to to search for an industry’s NACIS, SIC, and IRS Business Activity Code. The search results are shown in a table that lets you see the different categories at once, which really gives you a sense of the differences between the systems. (Wondering what an IRS Business Activity Code is? Check out this FAQ provided at the site just under the search box.) If you don’t know the code for your industry, see if you can find it. Keep the number handy. Love it, because it is your friend. It will surely pay off the next time you need to find out more about your industry!

Check back soon for the next Essential Sources installment, which will probably discuss a business directory or two…

[Edited on 6.23.09 to add hyperlinks – arh]


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2 Responses to Essential Sources: NAICS and SIC Manuals

  1. Anonymous says:

    Thanks for explaining their purpose and use so clearly.


  2. sandrar says:

    Hi! I was surfing and found your blog post… nice! I love your blog. 🙂 Cheers! Sandra. R.


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