A small business set-aside is a federal buy that only qualifying small businesses can compete for, and it's one of the main ways government contracts for small business get reserved. For a machine shop, the ones that matter are total small business set-asides and the four socio-economic programs: 8(a), HUBZone, service-disabled veteran-owned (SDVOSB) and women-owned (WOSB/EDWOSB). You qualify as "small" by the SBA size standard for the NAICS code on the buy, you represent your status in SAM.gov, and you find each small business set-aside on SAM.gov by filtering Contract Opportunities for the set-asides you actually qualify for.

Step one: check SBA size standards for the NAICS code

SBA assigns a size standard to each NAICS code. It defines the largest a business, together with its affiliates, can be and still compete for contracts reserved for small businesses. Per SBA, most manufacturing companies with 500 employees or fewer, and most non-manufacturing businesses with average annual receipts under $7.5 million, qualify as small, but there are exceptions by industry (SBA, Get started with contracting). The exact numbers are in 13 CFR 121.201 and SBA's table of size standards, and SBA's Size Standards Tool checks a specific code.

The important part: size is judged against the NAICS code on the solicitation, not just the one you think of as "your" code. A shop can be small under one code and not under another.

SBA also notes that you register in SAM.gov, where you certify eligibility for small-business contracts and represent whether you're women-owned, veteran-owned or located in an underutilized area.

Total small business set-asides and the rule of two

This is the most common set-aside a small shop will see. Under FAR 19.502-2:

• Buys above the micro-purchase threshold but not over the simplified acquisition threshold shall be set aside for small business, unless the contracting officer doesn't expect offers from two or more responsible small businesses that are competitive on fair market price, quality and delivery.
• Above the simplified acquisition threshold, the contracting officer sets the buy aside when there's a reasonable expectation of offers from at least two responsible small businesses and award at fair market prices.
• If only one acceptable small-business offer comes in, the contracting officer should award to that firm. If none come in, the set-aside is withdrawn and the requirement can be resolicited unrestricted.

That last point is why quoting matters even when you think you're the only small shop that can make the part.

8(a), HUBZone, SDVOSB and WOSB set-asides

Beyond total small business set-asides, each socio-economic program has its own FAR subpart and its own "reasonable expectation of two or more offers at a fair price" test:

• 8(a) Business Development Program. Created by Section 8(a) of the Small Business Act. SBA contracts with agencies and subcontracts to eligible participants, on a sole-source or competitive basis. Above the simplified acquisition threshold, contracting officers must consider 8(a) before a small business set-aside (FAR 19.800).
• HUBZone. Contracting officers may set aside buys above the micro-purchase threshold for HUBZone small businesses, and must consider a HUBZone set-aside before a HUBZone sole-source award or a small business set-aside (FAR 19.1305).
• SDVOSB. Same structure. Since January 1, 2024, the contracting officer verifies the offeror is designated in SAM as an SBA-certified SDVOSB, or represented SDVOSB status in SAM and applied to SBA for certification on or before December 31, 2023. Offerors who don't meet that are removed from consideration (FAR 19.1405).
• WOSB and EDWOSB. These set-asides apply in NAICS codes SBA has designated as underrepresented (EDWOSB) or substantially underrepresented (WOSB). You must be small under the solicitation's NAICS and either certified under 13 CFR 127.300 or have a pending certification application. The contracting officer checks SAM or DSBS (FAR 19.1505).

The practical takeaway: certification status in SAM is checked. Representing a status you haven't been certified for won't get your offer considered on SDVOSB or WOSB set-asides.

Two rules that catch shops and distributors

Limitations on subcontracting. On a supply contract under a set-aside, FAR 19.505(b) says a small business won't pay more than 50 percent of the amount the government pays for performance, excluding the cost of materials, to subcontractors that aren't similarly situated. If you plan to send most of the machining out, read this first. It applies to small business set-asides above the simplified acquisition threshold, and to 8(a), HUBZone, SDVOSB and WOSB set-asides regardless of dollar value.

The nonmanufacturer rule. If you supply an end item you didn't make, FAR 19.505(c) generally requires that you provide an item made by a small business in the U.S. or its outlying areas, have no more than 500 employees, be primarily engaged in retail or wholesale trade and normally sell that type of item, and take ownership or possession of it consistent with industry practice. Distributors quoting set-aside buys need to know who actually manufactured the part. On DLA parts, that often overlaps with approved source rules; see Approved Source on DIBBS: What AMSC B, C and D Mean.

How to find a small business set-aside on SAM.gov

1. Get your size right. Check your NAICS codes against SBA's size standards and keep your SAM.gov representations current.
2. Filter SAM.gov by set-aside. The core of how to find government contracts on SAM.gov: Contract Opportunities lets you filter by set-aside along with NAICS and PSC. Our SAM.gov contract opportunities search guide walks through the filters and alerts.
3. Watch DIBBS too. Most DLA spare-parts RFQs are posted on DIBBS, not SAM.gov, and the set-aside shows on the RFQ.
4. Check who else is small. Look up past awardees' CAGE records to see who you're up against. See the CAGE code lookup guide.

Where FedOpp fits

Your FedOpp Match Profile holds the set-asides you pursue (small business, SDVOSB, WOSB, HUBZone) along with NAICS and PSC/FSC codes. SAM.gov notices and DIBBS RFQs are checked against it, so a set-aside you don't qualify for shows up as a reason to skip instead of a surprise after you've priced the job. Set-aside and due date are on the DIBBS row. Set-aside is one gate; CMMC is another (see CMMC Level 1 Self-Assessment: A 2026 Guide for Small Shops). FedOpp doesn't determine your eligibility or size. That's SBA and your SAM.gov registration. If you want SAM.gov and DIBBS screened for your set-asides in one place, start a 7-day free trial. More background is in our guides.

Frequently asked questions

Do I need an SBA certification to bid a small business set-aside on SAM.gov?

For a total small business set-aside, SBA describes the requirement as meeting the size standard for the NAICS code and certifying your eligibility in your SAM.gov registration. SDVOSB and WOSB set-asides go further: FAR 19.1405 and 19.1505 require SBA certification or a qualifying pending application, and the contracting officer checks it.

What happens if I'm the only small business that bids on a set-aside?

Under FAR 19.502-2 and the matching program sections, if the contracting officer receives only one acceptable offer from a qualifying small business, the contracting officer should award to that firm.

Can I resell another company's part on a small business set-aside?

Possibly, but the nonmanufacturer rule in FAR 19.505(c) applies. The item generally has to be made by a small business in the U.S., and you must meet the size, trade and ownership/possession conditions.

Sources

• SBA, Get started with contracting (size standards, SAM registration)
• FAR 19.502-2, 19.505, 19.800, 19.1305, 19.1405, 19.1505 (acquisition.gov, FAC 2026-01)

Practical background for small suppliers, not legal advice. Size and eligibility are determined under SBA rules and the solicitation.

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