NAICS codes help describe the business activity associated with your company and opportunities, but they are not the same thing as SINs. Confusing the two can create bad targeting, weak applications, and mismatched expectations about what the contract actually authorizes you to sell.
How NAICS fits alongside SINs
| Classification | Main purpose | Why it matters |
|---|---|---|
| NAICS | Business activity classification | Used broadly in registrations, set-asides, and market context |
| SIN | MAS scope classification | Defines what your Schedule contract can actually offer |
| PSC | Procurement coding and buying context | Helps classify what agencies are acquiring |
The practical rule
Use NAICS to understand market and registration context, but use SINs to define contract scope. If your offer strategy is built from NAICS alone, you are usually one step removed from the actual MAS decision the reviewer is making.
Read next: SIN vs. NAICS vs. PSC, SIN categories, and contract requirements.