Your business is small. The SBA may disagree. Whether you legally qualify as a "small business" for a federal contract depends on a published size threshold tied to the specific NAICS code on the solicitation, not your general sense of company size.
> TL;DR: SBA size standards set the maximum number of employees or annual revenue a business can have and still qualify as "small" under a given NAICS code. The thresholds vary widely: an IT firm with 250 employees is small under NAICS 541512 (1,000-employee limit) but may not be under a different code. You must meet the size standard for the NAICS code listed on the contract, not just your own primary code. Affiliation rules can pull in the headcount or revenue of related businesses, which catches many firms off guard. Look up your threshold before you bid: SBA's size standards table and the SBA Size Standards Tool.
Why size standards exist
Federal law requires that a share of government contract dollars go to small businesses. The current statutory goal is 23% of prime contract awards. Set-asides are how contracting officers hit that number. A set-aside reserves a contract so only small businesses can bid, which means large primes are locked out.
For a set-aside to work, "small" has to mean something specific and verifiable. Size standards are the SBA's answer. They define exactly who is and isn't eligible, and they're codified at 13 CFR Part 121.
Without a clear standard, every contractor could claim small-business status and the set-aside system would collapse. The standards are also what the SBA uses to determine eligibility for programs like 8(a), HUBZone, WOSB, and SDVOSB. If you don't meet the size standard, you don't qualify for those certifications either.
How size standards are measured: employees vs. revenue
SBA uses two different measuring sticks depending on the industry.
Employee-based standards apply to most manufacturing and mining sectors. The SBA counts the average number of employees over the past 12 months, including full-time, part-time, and temporary workers. It also counts employees of affiliates (more on that shortly).
Revenue-based standards apply to most service, construction, retail, and wholesale industries. The SBA averages annual receipts over the past three years. "Receipts" generally means gross revenue, minus returns and allowances.
The reason for the split is practical. A manufacturing plant that makes $20 million per year might run 400 workers. A software consultancy at the same revenue might have 12. Using revenue for manufacturers and employees for service firms would produce nonsensical results in both directions, so the SBA uses whichever metric actually reflects competitive scale in that sector.
How to look up your size standard
Two tools, both free:
- SBA's Table of Small Business Size Standards at sba.gov/document/support-table-size-standards. This is a PDF spreadsheet covering every NAICS code. Download it, search by code or keyword, and read across to the threshold column.
- SBA Size Standards Tool at sba.gov/size-standards. Enter your NAICS code, your average annual revenue or employee count, and the tool tells you whether you qualify as small.
The table is updated periodically. The current version took effect March 17, 2023. Always confirm you're reading the current edition before submitting a bid.
The primary NAICS issue: your code vs. the contract's code
Here's the part most new contractors miss.
Your SAM.gov registration lists a primary NAICS code that reflects your main line of business. That code has its own size standard. But the size standard that matters for any specific contract is the NAICS code the contracting officer assigned to that solicitation, not your primary code.
A contract officer writing a solicitation for IT help-desk support might assign NAICS 541519 (Other Computer Related Services, 150 employees) instead of 541512 (Computer Systems Design Services, 1,000 employees). Same work, different code, very different size threshold. If your firm has 200 employees, you'd qualify under 541512 but not under 541519.
You should look up the size standard for the contract's NAICS code every time you bid, before you certify your size status in the offer. Misrepresenting your size is a federal violation. The consequences range from bid disqualification to debarment.
See NAICS codes for government contracts for a longer treatment of how NAICS assignments work and how to challenge a code you think is wrong on a solicitation.
Concrete size standard examples
The range across industries is wider than most people expect.
| Industry | NAICS Code | Size Standard |
|---|---|---|
| Computer Systems Design Services | 541512 | 1,000 employees |
| Other Computer Related Services | 541519 | 150 employees |
| General Building Construction (commercial) | 236220 | $45M avg annual receipts |
| Janitorial Services | 561720 | $22M avg annual receipts |
| Engineering Services | 541330 | $25.5M avg annual receipts |
| Management Consulting Services | 541611 | $24.5M avg annual receipts |
| Legal Services | 541110 | $12.5M avg annual receipts |
| Trucking (except local) | 484121 | 500 employees |
| Pharmaceutical Mfg. | 325412 | 1,250 employees |
| Architectural Services | 541310 | $12.5M avg annual receipts |
Source: SBA Table of Small Business Size Standards, effective March 17, 2023 (13 CFR Part 121).
The IT example matters in practice. A 250-person IT firm bidding on a NAICS 541512 contract is small and eligible. The same firm bidding on a NAICS 541519 contract is not. Whether the firm wins or loses may come down to whether the contracting officer coded the solicitation one way or the other. Knowing this before you bid, and knowing you can request a NAICS challenge under FAR Part 19.303, is not a small thing.
Affiliation rules: the trap that surprises experienced firms
The SBA's affiliation rules exist to prevent large businesses from setting up small subsidiaries to capture set-aside work. They're defined at 13 CFR 121.103, and they operate on a simple principle: if another business controls yours, or you control it, or you're both controlled by the same entity or individual, the SBA will count their size against yours.
Control can be established through equity, voting rights, overlapping officers and directors, or even a long-term exclusive contract that makes one business economically dependent on another. The SBA has found affiliation where two companies shared a family member as an officer, where a prior employer held a non-compete that effectively controlled a spinoff's customer base, and where an investor held a blocking minority stake.
What this means for your size calculation:
If the SBA determines you're affiliated with another business, it will combine your employee counts or revenue with that affiliate's numbers. A 40-person firm affiliated with a 600-person firm is now a 640-person firm for size purposes. That changes everything.
The most common affiliation scenarios that catch small contractors off guard:
- Mentor-protégé programs outside SBA's approved structure. If a large prime mentors your firm and controls how you do work, that can trigger affiliation. SBA-approved mentor-protégé agreements under 13 CFR 124.520 are exempt from affiliation, but informal relationships are not.
- Family-owned businesses. Two companies owned by spouses or close family members may be affiliated even if they operate in different industries.
- Investors with control rights. A venture or private equity investor holding board seats or protective provisions may trigger affiliation.
- SBA loans and LBOs. SBA examined whether certain leveraged structures created affiliation with lenders.
If you have any ownership complexity, get a size determination from your SBA district office before you bid on your first set-aside. A protest filed after award costs more than a pre-bid consultation.
What happens if you exceed the size standard during performance
Winning a small business set-aside doesn't lock in your eligibility forever.
Under FAR 52.219-28, the small business recertification clause, a contractor that was small at the time of award must recertify its size when the contract is novated to a successor, when a new option period is exercised on a contract over five years, or when the contracting officer requests a recertification for another reason.
If your business grows and you exceed the size standard, you can still complete the current contract period. You just can't recertify as small for subsequent option periods on that contract, and you can't use that contract's past performance to argue you were small during the period you weren't.
The rules are tighter for 8(a) contracts and HUBZone contracts, where exceeding the standard may trigger additional review. If you're in one of those programs, the SBA's size determination process (13 CFR 121.1001) applies.
Size protests can also be filed by other offerors after award. A competitor who believes you're not actually small can file a protest with the contracting officer within five business days of award notification. The SBA will then make a formal size determination. If they find you're not small, the award can be rescinded.
Size standards and set-aside eligibility
Size standards are the entry-level filter. Passing the size standard makes you "small." But the socioeconomic set-asides (8(a), HUBZone, WOSB, SDVOSB) require additional certifications on top of that. You have to be small AND certified.
The size standard that applies to 8(a) and HUBZone certifications is tied to your primary NAICS, or in some cases the industry in which you claim to primarily operate. For set-aside contract bids, it's always the contract's NAICS code.
If you're not sure which certifications your business might qualify for, the certification quiz at SupplierDiversity.com takes about four minutes and surfaces the programs worth pursuing based on your business type, location, and ownership.
For a broader look at how set-asides actually work in federal contracting, see federal set-asides explained.
Frequently asked questions
Does my size standard change if I'm bidding on a subcontract instead of a prime contract?
For prime contracts on set-asides, you must be small under the contract's NAICS code. For subcontracts, the rules are more flexible. The prime contractor's small business subcontracting plan (required on large contracts over certain thresholds under FAR 19.702) credits subcontracts to small businesses, but there's no automatic size certification requirement from the subcontractor's perspective for most subcontracts. Some specific programs have their own subcontract size requirements, so check the prime's flow-down clauses.
Can I challenge the NAICS code a contracting officer assigned to a solicitation?
Yes. Under FAR 19.303, an offeror can appeal the NAICS code designation to the SBA's Office of Hearings and Appeals (OHA). The appeal must be filed within ten calendar days of the solicitation's issuance. The OHA will determine whether the contracting officer's code was appropriate for the principal purpose of the acquisition. Winning a NAICS challenge changes the size standard that applies to the solicitation.
What is a "self-certification" and how does it work?
When you submit a bid on a set-aside, you certify in your offer that your business is small under the contract's NAICS code. There's no pre-approval process. The SBA doesn't verify every bid. The system runs on self-certification, which is why the penalties for misrepresentation (18 U.S.C. 1001 and the False Claims Act) are serious. A competitor or contracting officer can trigger a formal SBA size determination at any time.
My business just crossed the size threshold. Am I disqualified from all small business programs?
Not necessarily, and not immediately. Contracts already awarded continue to completion. Your eligibility for new solicitations depends on whether you're above the threshold for that contract's NAICS code at the time you certify. Different NAICS codes have different thresholds, so you may still qualify as small for some types of work even if you've exceeded the threshold for your primary code.
Where does my NAICS code come from, and can I have more than one?
You select your primary NAICS code when you register in SAM.gov, and you can add secondary codes that reflect additional lines of work your business performs. The primary code is used for certain eligibility determinations. But for any specific contract bid, the code that matters is the one the contracting officer put on the solicitation. Use the NAICS code lookup tool at SupplierDiversity.com to find the right code for your work before you register or bid.
Last reviewed: June 2026
