NAICS Codes for Government Contracting: How to Find and Use Yours

Every federal contract opportunity starts with a six-digit number. That number is a NAICS code, and if your business does not have the right ones, you are invisible to the $700+ billion federal contracting market. Contracting officers use NAICS codes to categorize procurements, determine small business eligibility, and find qualified vendors. Getting your NAICS code selection right is not a minor administrative task -- it is a strategic decision that shapes which contracts you can pursue and whether you qualify as a small business to win them.

Despite their importance, NAICS codes are one of the most misunderstood elements of government contracting. Businesses pick too few codes and miss relevant opportunities. They pick too many and dilute their profile. They choose the wrong primary code and accidentally disqualify themselves from small business set-asides worth over $160 billion annually.

This guide explains what NAICS codes are, why they matter for government contracting, and exactly how to find and select the right codes for your business. Whether you are registering on SAM.gov for the first time or refining an existing profile, the strategies here will help you compete more effectively.

What Is a NAICS Code?

The North American Industry Classification System (NAICS) is the standard framework used by the United States, Canada, and Mexico to classify business establishments by industry. Each NAICS code is a six-digit number that identifies a specific type of economic activity.

The system was developed in 1997 to replace the older Standard Industrial Classification (SIC) system. The U.S. Census Bureau maintains the official NAICS code list and updates it every five years to reflect changes in the economy. The most recent revision took effect in 2022.

How NAICS Codes Are Structured

NAICS codes follow a hierarchical structure that moves from broad to specific:

First two digits: Economic sector (20 broad sectors total)
Third digit: Subsector
Fourth digit: Industry group
Fifth digit: NAICS industry
Sixth digit: National industry (U.S., Canada, or Mexico specific)

For example, take NAICS code 541512 -- Computer Systems Design Services:

54: Professional, Scientific, and Technical Services (sector)
541: Professional, Scientific, and Technical Services (subsector)
5415: Computer Systems Design and Related Services (industry group)
54151: Computer Systems Design and Related Services (industry)
541512: Computer Systems Design Services (national industry)

This structure matters because contracting officers assign NAICS codes at the six-digit level. Two businesses that both consider themselves "IT companies" might fall under completely different NAICS codes depending on whether they provide custom software development (541511), computer systems design (541512), or data processing services (518210).

NAICS Codes vs. PSC Codes

You will encounter another classification system in government contracting: Product and Service Codes (PSC). These are different from NAICS codes, and both serve distinct purposes.

NAICS codes classify what your business does -- your industry. They determine your small business size standard and appear on your SAM.gov registration.

PSC codes classify what the government is buying -- the specific product or service in a particular contract. They are assigned by the contracting officer to individual procurements.

Both codes appear on contract opportunities. You need the right NAICS codes in your SAM.gov profile to be found, and you need to understand PSC codes to identify specific opportunities that match your capabilities.

Why NAICS Codes Matter for Government Contracting

NAICS codes are not just a classification exercise. They have direct, measurable impact on your ability to win government contracts. Here are the three ways they shape your contracting success.

1. NAICS Codes Determine Your Small Business Status

This is the single most important reason to care about NAICS codes. The Small Business Administration (SBA) assigns a size standard to every NAICS code, and that size standard determines whether your company qualifies as a "small business" for contracts under that code.

Size standards vary dramatically by industry. Some examples:

NAICS 541511 (Custom Computer Programming): $34 million in average annual receipts
NAICS 541330 (Engineering Services): $25.5 million in average annual receipts
NAICS 236220 (Commercial Building Construction): $45 million in average annual receipts
NAICS 561210 (Facilities Support Services): 850 employees
NAICS 561612 (Security Guards and Patrol Services): $29 million in average annual receipts

A company with $30 million in annual revenue qualifies as small under NAICS 541511 but does not qualify under NAICS 541330. The NAICS code assigned to a specific contract -- not the one you prefer -- determines which size standard applies.

This matters because of the federal government's 23% small business contracting goal, which translates to more than $160 billion in annual set-aside spending. If you lose your small business status under a particular NAICS code, you cannot compete for set-aside contracts in that category. You can look up the current size standards for any NAICS code on the SBA website.

For a deeper look at how small business status connects to certifications like 8(a), WOSB, and HUBZone, each of those programs uses your NAICS-based size standard as the baseline eligibility requirement.

2. NAICS Codes Control Which Opportunities You See

When contracting officers create solicitations, they assign a NAICS code to each one. This code tells vendors what industry the work falls into and which size standard applies for small business determinations.

Government buyers also search SAM.gov to find potential vendors. Your NAICS code selections directly affect whether you appear in their searches. If a contracting officer is looking for vendors under NAICS 541519 (Other Computer Related Services) and you only have 541512 (Computer Systems Design Services) in your profile, they will not find you -- even if you are perfectly qualified to do the work.

When you search for contracts on SAM.gov or other procurement platforms, NAICS codes are one of the primary filters. Having the right codes in your profile means you will see relevant opportunities in your automated searches and email alerts.

3. NAICS Codes Affect Contract Vehicle Eligibility

Many government contract vehicles -- including GSA Schedules, GWACs, and BPAs -- are organized by NAICS code. When agencies establish contract vehicles, they specify which NAICS codes are covered.

If your target contract vehicle requires NAICS 541511 and you have only listed 541512 in your SAM.gov profile, you may not be eligible to compete for a spot on that vehicle. Getting your NAICS codes right early prevents this kind of missed opportunity later.

How to Find Your NAICS Code

Finding the right NAICS codes for your business requires research, not guesswork. Here is a systematic approach that works.

Step 1: Start With the Official NAICS Search Tool

The U.S. Census Bureau maintains the official NAICS code lookup tool. This is your primary resource. Start by entering keywords that describe your business activities -- not your job title or company name, but what your business actually does.

For example, if you run a cybersecurity firm, search for terms like:

"Computer security"
"Information security"
"Cybersecurity"
"Security consulting"

The search tool will return matching NAICS codes with their full descriptions. Read the descriptions carefully. The code title alone can be misleading -- the full description and cross-references tell you whether a code truly fits your business.

Step 2: Review the Full Code Descriptions

Each NAICS code comes with a detailed description that includes:

What the industry comprises: The core activities covered
Cross-references: Related codes you should also consider
Exclusions: Activities that specifically do not belong in this code

The cross-references are especially valuable. They point you to adjacent codes you might not have considered. A company providing IT staffing might initially look at NAICS 541512 (Computer Systems Design) but discover through cross-references that 561311 (Employment Placement Agencies) or 541611 (Administrative Management Consulting) are better fits for parts of their business.

Step 3: Research What Your Competitors Use

Look at the SAM.gov profiles of companies that do similar work. Their NAICS code selections can reveal codes you overlooked and validate codes you are considering.

To do this:

Go to SAM.gov and use the entity search
Find competitors or similar companies in your industry
Review their registered NAICS codes
Note which codes appear most frequently across multiple similar companies

This competitive research also shows you who you will be competing against under each NAICS code. If your direct competitors are all registered under 541511 but you chose 541519, you are in a different competitive pool -- which could be an advantage or a missed opportunity depending on the contract landscape.

Step 4: Review Past Contract Awards

Search the Federal Procurement Data System (FPDS) or USASpending.gov for contracts similar to work you want to perform. Each award record includes the NAICS code assigned by the contracting officer.

This reveals how the government actually categorizes the type of work you do, which sometimes differs from how you would categorize it yourself. If most janitorial services contracts in your region are awarded under NAICS 561720 (Janitorial Services) rather than 561210 (Facilities Support Services), you know which code to prioritize.

Understanding past awards is also essential when you start searching for new contract opportunities. The NAICS codes on historical awards tell you where future opportunities are most likely to appear.

Step 5: Consult the SBA Size Standards Table

After identifying candidate NAICS codes, check the SBA size standard for each one. This step serves two purposes:

Confirms your small business eligibility under each code
Reveals strategic implications of choosing one code over another

If your company's average annual receipts are $20 million, you qualify as small under codes with a $25.5 million threshold but not under codes with a $16.5 million threshold. This financial reality should influence your code selection strategy.

NAICS Code Selection Strategies

Choosing your NAICS codes is not just about finding accurate descriptions. It is about positioning your business to compete effectively for the contracts you want to win.

Choose a Primary NAICS Code Carefully

Your primary NAICS code in SAM.gov is the one that represents your main business activity. This is the code that contracting officers see first, and it sets the default size standard for your business when size is evaluated outside a specific procurement context.

Your primary code should reflect where you generate the most revenue or where you intend to focus your government contracting efforts. These are not always the same thing. A company that earns most of its revenue from commercial IT consulting but wants to pursue government cybersecurity contracts might choose a cybersecurity-focused primary code.

Add Secondary Codes Strategically

SAM.gov allows you to list multiple NAICS codes. There is no official limit, but more is not automatically better. Each additional code should represent work your company can actually perform and actively wants to pursue.

A good rule of thumb: list 5-10 NAICS codes that cover your core capabilities and adjacent services. This gives you broad visibility without making your profile look unfocused.

For each secondary code, ask yourself:

Can we deliver this service today with our current team and capabilities?
Have we performed this type of work before (commercially or for government)?
Do we want to actively pursue contracts under this code?
Do we qualify as a small business under this code's size standard?

If you cannot answer yes to at least the first and last questions, reconsider adding the code.

Think About the Competitive Landscape

Some NAICS codes are extremely crowded. NAICS 541512 (Computer Systems Design Services) has tens of thousands of registered vendors on SAM.gov. Other codes in similar technical areas have far fewer competitors.

This does not mean you should avoid popular codes -- those codes usually have the most contract dollars available. But if you can legitimately claim a less competitive adjacent code, you face fewer competitors for the contracts awarded under it.

For businesses just getting started in government contracting, selecting strategic NAICS codes can be the difference between competing against 50 firms and competing against 5,000.

Align With Target Contract Types

If you have identified specific types of contracts you want to pursue -- whether easier entry-point contracts or larger multi-year vehicles -- research the NAICS codes those contracts typically use. Then ensure those codes are in your SAM.gov profile before you start pursuing them.

This alignment between your NAICS codes and your business development targets is fundamental. It sounds obvious, but a surprising number of companies discover they are missing a critical NAICS code only after they find the perfect opportunity and realize they are not set up to compete for it.

Common NAICS Code Mistakes

After working with businesses entering the government contracting space, certain mistakes appear repeatedly. Avoiding these will save you time and missed opportunities.

Mistake 1: Choosing Only One NAICS Code

Your business almost certainly performs work that spans multiple NAICS codes. Listing only your primary code means you are invisible to contracting officers searching for vendors under your other legitimate capabilities. Most established government contractors list between 5 and 15 codes.

The opposite extreme is equally problematic. Listing 30 or 40 NAICS codes signals to contracting officers that you are either unfocused or padding your profile. It also dilutes your relevance in search results. Stick to codes where you have genuine capability and interest.

Mistake 3: Ignoring Size Standard Implications

Adding a NAICS code where you exceed the size standard does not directly harm you. But if a contracting officer evaluates your size under that code for a set-aside contract, you will not qualify. Worse, if you self-certify as small and then cannot substantiate it during a size protest, you face potential penalties.

Always verify your size status under each NAICS code you add. This is particularly important for companies approaching size standard thresholds.

Mistake 4: Never Updating Your NAICS Codes

Your business evolves. Your NAICS codes should evolve with it. The SBA revises size standards periodically, and the Census Bureau updates NAICS codes every five years. A code that was perfect three years ago might not reflect your current capabilities, and a size standard you once exceeded might have been raised to include you.

Review your NAICS code selections at least annually -- ideally when you renew your SAM.gov registration.

Mistake 5: Choosing Based on Title Alone

NAICS code titles can be deceptive. "Other Computer Related Services" (541519) sounds like a catch-all, but its official description covers specific activities that may or may not match your work. Always read the full description, examples, and exclusions before adding a code.

Mistake 6: Confusing Revenue Source With Service Delivery

A staffing agency that places IT professionals might naturally gravitate toward IT NAICS codes like 541512. But if the company's actual service is placing temporary employees, the more accurate code could be 561320 (Temporary Help Services). The work your employees perform at client sites is not the same as the service your company provides.

Contracting officers and the SBA evaluate this distinction carefully. Choose codes that match what your company delivers as a business entity, not the technical skills of your workforce.

How NAICS Codes Fit Into Your SAM.gov Registration

NAICS code selection is one of the most critical steps in your SAM.gov registration process. Here is how the two connect.

When You Select NAICS Codes During Registration

During SAM.gov registration, you will reach a section that asks you to identify your NAICS codes. You must select at least one code, and you will designate one as your primary NAICS code. The registration system allows you to search for codes by keyword or browse the full hierarchy.

What the Government Sees

Your NAICS codes appear prominently in your SAM.gov entity profile. Contracting officers searching for vendors filter by NAICS code, so your selections directly control your visibility. The profile also displays the SBA size standard associated with each code and your self-certified size status.

Updating Your NAICS Codes After Registration

You can update your NAICS codes at any time by logging into SAM.gov and modifying your entity registration. Changes take effect after the system processes your update, which typically happens within a few business days.

The registration itself must be renewed annually. SAM.gov registration takes 10-15 business days to process when submitted correctly, and your registration expires if not renewed. Use each annual renewal as an opportunity to audit and update your NAICS code selections.

Industry-Specific NAICS Code Guidance

Different industries have unique considerations when selecting NAICS codes. Here are some of the most common sectors in government contracting and the codes to evaluate.

Information Technology

The IT sector has one of the most fragmented NAICS code landscapes. Key codes include:

541511: Custom Computer Programming Services
541512: Computer Systems Design Services
541513: Computer Facilities Management Services
541519: Other Computer Related Services
518210: Computing Infrastructure Providers, Data Processing, and Related Services
511210: Software Publishers

Most IT companies legitimately span multiple codes. The key is matching each code to a specific service line your company delivers.

Professional Services and Consulting

541611: Administrative Management and General Management Consulting
541612: Human Resources Consulting Services
541618: Other Management Consulting Services
541690: Other Scientific and Technical Consulting Services
541990: All Other Professional, Scientific, and Technical Services

Consulting firms often struggle because their work crosses multiple code boundaries. Focus on the type of consulting you perform, not the industries you serve.

Construction and Facilities

236220: Commercial and Institutional Building Construction
238210: Electrical Contractors
238220: Plumbing, Heating, and Air-Conditioning Contractors
561210: Facilities Support Services
561720: Janitorial Services

Construction and facilities management NAICS codes frequently use employee count rather than revenue as the size standard, which changes the eligibility calculation for many firms.

621111: Offices of Physicians
621999: All Other Miscellaneous Ambulatory Health Care Services
624190: Other Individual and Family Services
541714: Research and Development in Biotechnology

Healthcare companies entering government contracting should pay special attention to whether their work falls under healthcare delivery codes or consulting codes, as the size standards differ significantly.

Frequently Asked Questions

How many NAICS codes can I have on my SAM.gov registration?

There is no hard limit on the number of NAICS codes you can list in SAM.gov. However, quality matters more than quantity. Most successful government contractors list between 5 and 15 codes that accurately reflect their core business activities. Listing too many codes makes your profile appear unfocused, while too few limits your visibility to contracting officers.

Can I change my NAICS codes after registering on SAM.gov?

Yes. You can log into SAM.gov and update your NAICS codes at any time. Changes are processed within a few business days. You should review your NAICS code selections at least once a year during your annual SAM.gov renewal to ensure they still reflect your current capabilities and business direction.

What happens if I pick the wrong NAICS code?

Choosing an inaccurate NAICS code can have several consequences. You might miss contract opportunities because contracting officers search by NAICS code. You could lose small business eligibility if the code's size standard is lower than your company's revenue or employee count. In worst-case scenarios, misrepresenting your NAICS code on a set-aside contract could trigger a size protest, potentially resulting in loss of the award.

Can a contracting officer assign a different NAICS code than what I have in my SAM.gov profile?

Yes. Contracting officers assign the NAICS code for each individual solicitation based on the principal purpose of the work. Their assignment determines the size standard for that procurement, regardless of what NAICS codes you have listed in your profile. If you disagree with the assigned NAICS code, you can appeal to the SBA Office of Hearings and Appeals before the solicitation closes.

Do state and local government contracts use NAICS codes?

Many state and local procurement systems reference NAICS codes, but it is not universal. Some states use NAICS codes directly in their vendor registration portals. Others use SIC codes, NIGP commodity codes, or their own classification systems. If you are pursuing state and local contracts alongside federal work, check each jurisdiction's requirements separately.

What is the difference between a NAICS code and a CAGE code?

A NAICS code classifies your business industry and activities. A CAGE (Commercial and Government Entity) code is a unique five-character identifier assigned to your business during SAM.gov registration. CAGE codes identify who you are; NAICS codes identify what you do. Both are required for government contracting but serve completely different purposes.

How do NAICS codes affect my ability to get small business certifications?

Every SBA small business certification -- including 8(a), WOSB, SDVOSB, and HUBZone -- uses NAICS-based size standards as the foundation for eligibility. You must qualify as small under the size standard for your primary NAICS code to be eligible for these programs. If your company grows past the size standard threshold, you risk losing both your small business status and your certifications for contracts under that code.

Should I use the most specific six-digit NAICS code or a broader category?

Always use the six-digit code. Government solicitations are assigned at the six-digit level, and that is the level at which size standards are defined. Broader categories (four or five digits) are useful for understanding the NAICS hierarchy, but your SAM.gov registration and your strategic planning should focus on the specific six-digit codes.

Moving Forward With the Right NAICS Codes

Getting your NAICS codes right is one of those foundational steps in government contracting that pays dividends for years. The codes you select today determine which contracts you see, whether you qualify as a small business, and how contracting officers find you when they search for vendors.

Here is your action plan:

Research your codes using the Census Bureau NAICS lookup tool and competitor analysis on SAM.gov
Verify size standards for each code against your company's current revenue and employee count at the SBA website
Select 5-10 codes that accurately reflect your capabilities and align with contracts you want to pursue
Designate your primary code based on your main business activity or primary contracting focus
Update your SAM.gov profile and review your selections annually

NAICS codes are one piece of a larger government contracting strategy that includes registration, certifications, opportunity identification, and proposal development. Each element builds on the others, and getting the fundamentals right early prevents costly mistakes later.

If navigating NAICS codes, SAM.gov registration, and government contracting strategy feels overwhelming, SLED.AI helps businesses build their federal contracting foundation correctly from day one. From NAICS code selection to full SAM.gov registration and beyond, our team ensures you are positioned to compete for the contracts your business deserves.