What you will learn
- NAICS (six digits) classifies the industry; the contracting officer assigns one code to each requirement and it sets the small business size standard for that buy.
- PSC (four characters) classifies the product or service; services start with a letter, products with a number. It does not affect size, but it is how spend is reported and searched.
- Your size status can be small under one NAICS and other-than-small under another. Check the standard for the code on the notice, not your primary code.
- Search opportunities by NAICS and PSC together. Offices are inconsistent with keywords and titles; they are consistent with codes.
- A wrong NAICS on a solicitation can be challenged, but only within 10 days of the solicitation being issued (
13 CFR 121.1103).
Chapter 01of 051 min
Two code systems, two questions
Federal procurement classifies every requirement twice. The North American Industry Classification System code answers "what industry does this work belong to". The Product Service Code answers "what exactly is being bought". A help desk contract might carry NAICS 541512 (Computer Systems Design Services) and PSC D310 (IT and telecom: cyber security and data backup) or D399 (IT and telecom: other). The two are assigned independently by the contracting officer, and they serve different purposes downstream.
| NAICS | PSC | |
|---|---|---|
| Format | Six digits (541512). The first two are the sector, more digits narrow the industry. | Four characters. Services start with a letter (D, R, J); products with a number (70, 58). |
| Who maintains it | The US Census Bureau with Canada and Mexico; revised every five years. | The General Services Administration, in the Federal Procurement Data System manual. |
| What it decides | The small business size standard for the buy, and therefore set-aside eligibility. | How the buy is categorized for spend analysis, category management and search. |
| Where you set yours | In SAM.gov assertions: one primary, any number of secondary. | Optional in SAM; searchable on SAM.gov and other tools. |
| Why it matters to you | Bid eligibility and the SBA size determination. | Finding notices that keywords and NAICS miss; reading award history by what was bought. |
Chapter 02of 051 min
How the NAICS code sets your size
Every NAICS code has a size standard published by the Small Business Administration in 13 CFR 121.201: either an annual receipts ceiling (for most services, measured as the average over your last five completed fiscal years under 13 CFR 121.104) or an employee ceiling (for most manufacturing, measured as the average over the last 24 months). You are small for a given solicitation if you, together with your affiliates, are under the standard for the NAICS the contracting officer assigned to that solicitation.
The consequence is easy to miss: the same company can be small under NAICS 541611 (Administrative Management and General Management Consulting, a receipts standard) and other-than-small under NAICS 541512 (a different receipts standard), or vice versa. Do not assume your primary code's status applies everywhere. Read the standard for the code on the notice.
Chapter 03of 051 min
Choosing your codes
- 1
Pick one primary NAICS that describes most of your revenue
It goes first in SAM and on your capability statement. Choose the code your best past performance actually falls under, not the one with the largest size standard.
- 2
Add secondary codes where you have real experience
Contracting officers and small business specialists look at your codes to decide whether to invite you. A long list of codes with no supporting past performance reads as unfocused; five to ten well-chosen codes read as credible.
- 3
Record the size standard next to each code
Keep a simple table: code, description, standard, your status, the year you last checked. Review it when SBA revises standards or your receipts change.
- 4
Map the PSCs that pair with your NAICS codes
Search recent awards in your NAICS codes and note the PSCs on them. A services company will usually find three to six recurring PSCs. Those become your search filters.
- 5
Check the codes competitors and incumbents carry
Award notices show both codes. If the incumbent on a contract you want is registered under codes you are missing, add them.
Chapter 04of 051 min
Searching with both codes
Keywords fail because offices describe the same work differently; codes hold steady. The most reliable opportunity search is a NAICS filter, a PSC filter, a set-aside filter matched to your certifications, and only then keywords to catch outliers. The SAM.gov guide walks through building the saved searches.
Primary NAICS: 541512 Computer Systems Design Services (receipts standard checked 2026) Secondary: 541513 Computer Facilities Management; 541519 Other Computer Related Services; 541611 Administrative Management Consulting PSCs that recur on our awards: D302 IT systems development; D307 IT strategy and architecture; D310 cyber security and data backup; D399 IT and telecom, other; R408 program management support
Chapter 05of 051 min
When the NAICS on a solicitation is wrong
If a solicitation carries a NAICS code that does not describe the principal purpose of the work, and the choice affects your eligibility, you may appeal the assignment to the SBA Office of Hearings and Appeals. The appeal must be filed within 10 calendar days after the solicitation is issued, or 10 days after an amendment that changes the code (13 CFR 121.1103). Ask the contracting officer first; a question during the Q&A period sometimes prompts a correction without an appeal.
Code hygiene
- Primary NAICS matches your largest revenue line and your best past performance.
- Every secondary code has at least one supporting past performance.
- Size standard and your status recorded for each code, reviewed yearly.
- Recurring PSCs identified from your award history and used in saved searches.
- SAM assertions and your capability statement list the same codes.
- Q&A deadline noted on every solicitation so a wrong code can be questioned in time.
Before you go
Questions people ask
- How many NAICS codes should a small business register?
- As many as you can support with experience, usually five to ten. Registration under a code does not make you eligible for anything by itself; the contracting officer's code on the solicitation and your size under it do.
- Does the PSC affect my small business status?
- No. Only the NAICS code carries a size standard. The PSC is used for categorizing and reporting what was bought.
- Where do I find the size standard for a code?
- In the SBA size standards table at 13 CFR 121.201, published on sba.gov and searchable by code. SAM.gov also shows your status by code once your size metrics are entered.
- What if the same work appears under different NAICS codes from different agencies?
- That is common. Register under each code you see used for your services, and search by PSC as well, because the PSC is often more consistent across agencies than the NAICS.
- Can a NAICS code change after award?
- The code on a contract stays with it, but size can be re-examined at option exercise or on long-term contracts under SBA rules on recertification. Know the rules on your contract before you grow past a standard.
NAICS and PSC tree filters with a match score
ProposalWorkspace lets you filter SAM.gov opportunities by hierarchical NAICS and PSC trees, set-aside, agency, place of performance and due date, and scores every notice against the codes and profile you maintain, so the opportunities that fit your registration surface first and the ones you cannot bid never take your time.
Up next
8(a), HUBZone, SDVOSB and WOSB: which small business certification fits you
Set-asides move about a quarter of federal contract dollars to small businesses, and most of that flows through four certifications. Each has a different test, a different reward and a different cost to maintain. This guide compares them so you can decide which to pursue and in what order.
6 min
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This guide is general information for federal contractors drawn from the FAR and standard capture and proposal practice. It is not legal advice; always read the specific solicitation and consult counsel on protests, contract terms and compliance questions.