It’s impossible to get very far in the GSA Schedule acquisition process without encountering the acronym “SIN.” Special Item Numbers (SINs) are of critical importance to the GSA, but can be confusing to new contractors. Much of this confusion arises from the relationship between SINs and North American Industry Classification System (NAICS) Codes, which many contractors are already familiar with. Here at Winvale, we receive many questions about SINs, NAICS Codes, and the differences between them—so let’s break that down.
What are NAICS Codes and SINs?
A NAICS Code (short for North American Industry Classification System) is a six-digit numeric code that describes the core of a company’s business. These digits indicate the economic sector, subsector, industry group, NAICS industry, and national industry that best describe your business. NAICS Codes have several purposes, such as determining whether a business is small or large. You can also use NAICS Codes to help identify opportunities for your business. If you’ve worked with the government in any capacity, you’ve likely encountered NAICS Codes before, but you may be less familiar with Special Item Numbers, or SINs.
SINs were created by GSA as a way of categorizing the products and services offered on GSA Schedules. Offerings are sorted first by large category, then subcategory, and finally by SIN. Each SIN has a specific scope that defines exactly what products and services may be offered under that SIN. Now that we have a basic understanding of what NAICS Codes and SINs are, let’s dive a little deeper into the differences between them.
What are the Differences Between NAICS Codes and SINs?
The biggest difference between NAICS Codes and SINs is that SINs are specific to GSA. NAICS Codes are used by any business, not just GSA Schedule holders. Related to this, SINs only describe products being offered on the GSA Schedule, not all products offered by a company. For example, if your business offers a software product as well as a software training course, but you only intend to sell the software product on the GSA, you would only need to pursue the SIN relevant to the product—not the training course.
It’s important to only select SINs for products or services you actually intend to offer on the GSA—don’t add SINs simply because they relate to your business. Recently, the GSA cross-walked SINs and NAICS Codes so that they correspond more closely to each other. While this can help you identify which SIN to pursue, it’s also a source of confusion for many contractors. Because NAICS Codes and SINs often have the same digits, contractors may mix them up. Next, we’ll talk about some of the most common sources of confusion when it comes to NAICS Codes and SINs.
Why are NAICS Codes and SINs Easily Confused?
While NAICS Codes and SINs ultimately serve different purposes, they are closely related to one another, which can make it difficult to differentiate them. For example, in order to pursue a SIN, you must have that SIN’s corresponding NAICS Code active on your SAM.gov account. However, adding a SIN to your proposal or contract is not as easy as simply adding the NAICS Code to your SAM.gov account.
It’s important to keep in mind that adding a NAICS Code to your SAM.gov account does not have any effect by itself. All it does is allow you to pursue a SIN. Only once the SIN is awarded can you begin selling those products or services on your GSA Schedule.
Another aspect of confusion is that some NAICS Codes correspond to more than one SIN. This is because SINs are sometimes more specific than NAICS Codes. For example, NAICS Code 339920 (Sporting and Athletic Goods Manufacturing) corresponds to three different SINs: 339920, 339920S, and 339920PARK.
These SINs are for target systems and range accessories, sporting goods equipment, and playground equipment respectively. All of these products fall under NAICS 339920, but they’re split into three different SINs under the GSA.
What this means for contractors is that having a certain NAICS Code does not mean you are eligible to add a certain SIN to your contract. If your company only manufactures playground equipment, your primary NAICS Code would likely be 339920—but this does not mean that you can add SIN 339920, as it only covers target systems and target range accessories. Essentially, while corresponding NAICS Codes are a helpful place to start when determining which SINs to pursue, they are not the only thing to consider.
Do You Need Help with Your GSA Schedule?
Understanding the differences between NAICS Codes and SINs is critical, because they both play important roles in the GSA Schedule process. If you find that you’re still confused by the two, check out our blogs on the topic, like NAICS Codes 101 in 2024 and How to Choose the Right SIN. If you are looking to get a GSA Schedule and don’t know where to start, whether it’s determining NAICS Codes, SINs, or crafting the GSA Schedule proposal itself, our consultants are here to help.
