Set-Asides Explained: 8(a), WOSB, HUBZone, SDVOSB, and the Rest

Updated July 12, 2026 3 min read

A set-aside is not a certification. It is a label the government puts on a specific contract, restricting who can even submit a bid. The certifications (8(a), WOSB, HUBZone, SDVOSB) are what let a business compete for contracts carrying that label. The label itself is a separate decision, made contract by contract, before your certification ever matters.

That distinction trips up a lot of first-time bidders. You can hold every certification in the book and still lose to someone who reads the solicitation type more carefully than you did. Here is the actual roster.

Small business set-aside

The baseline category. Any contract expected to fall under a certain dollar threshold gets automatically reserved for small businesses if at least two qualified small businesses are likely to bid at a fair price. That's the Rule of Two, and it applies before any of the more specific categories below even come into play. No special certification required, just a size standard your business has to meet for its NAICS code.

8(a) Business Development set-aside

Reserved for businesses in the SBA's 8(a) Business Development Program. Some 8(a) contracts are competed only among other 8(a) firms. Others are sole-source, meaning the contracting officer can award it to one 8(a) business directly, no competition. That sole-source authority is what makes 8(a) different in kind from the other categories, not just in eligibility test.

Women-Owned Small Business (WOSB) set-aside

Reserved for businesses that meet the WOSB ownership and control test, and only in industries where SBA has determined women-owned businesses are underrepresented. A further tier, Economically Disadvantaged WOSB (EDWOSB), opens up a wider set of contracts by adding an economic-disadvantage requirement on top.

HUBZone set-aside

Reserved for businesses with a principal office in a Historically Underutilized Business Zone and a workforce that meets HUBZone residency requirements. HUBZone also carries a price-evaluation preference in full and open competitions, on top of its own set-aside category, so it shows up in two different ways in a solicitation, not just one.

Service-Disabled Veteran-Owned Small Business (SDVOSB) set-aside

Reserved for businesses at least 51 percent owned and controlled by one or more veterans with a service-connected disability rated by the VA. Like 8(a), SDVOSB contracts can also be sole-sourced under specific dollar thresholds, not just competed.

Total vs. partial set-asides

Two more terms that show up in the solicitation itself, independent of which category above applies. A total set-aside means the whole contract is restricted, full stop. A partial set-aside splits a larger requirement into pieces, some reserved for small businesses (or a specific category) and some open to full and open competition. You'll see this on bigger multiple-award contracts more than on a single small buy.

Where this actually shows up

On SAM.gov, the "Set-Aside Type" field on a solicitation is where all of this lands in practice. It's easy to skim past. It's also the single field that tells you whether you're even allowed to submit, before you spend an afternoon reading the rest of the document.

Reading that field first, before anything else in the solicitation, is a habit worth building early.

We are not SAM.gov, are not affiliated with the U.S. government, and are not a registrar. SAM.gov registration is always free at sam.gov. Certification and set-aside eligibility determinations are made by the SBA and the contracting officer, not by us.

We built our pipeline to flag set-aside type on every solicitation we pull, so you're not hunting for that field manually on every listing. You can see how that scoring works on our features page.