How to File an SBA Size Protest

If you lost a small-business set-aside to a company you do not believe is actually small, you can challenge it with an SBA size protest — but in most cases it must reach the contracting officer within five business days of the moment you learn who won.

Check first: before you spend energy challenging someone else's status, make sure your own house is in order. Our free 60-second eligibility checker confirms which set-aside programs and size standards your business actually qualifies for.

This guide walks through the whole process: what an SBA size protest is, who is allowed to file one, exactly how long you have, what to put in it, and what happens once the SBA has it. The theme running through all of it is speed — the window to act is measured in business days, and missing it ends the matter before it starts.

What an SBA size protest actually is

A size protest is a formal request asking the SBA to determine whether a particular company qualifies as a small business for a specific contract. It comes up when an award is set aside for small businesses (or a socioeconomic category built on small-business status, like WOSB or HUBZone) and a competitor believes the apparent winner is, in reality, too big — usually because of affiliation with a larger company, or because its revenue or headcount has crossed the applicable size standard.

Two things make the size protest distinct, and both trip people up. First, it is decided by the SBA, not by the contracting agency and not by the Government Accountability Office. A size protest filed with the GAO will not be heard there. Second, it is narrow: a size protest is only about whether the firm is small. It is not the vehicle for arguing the agency scored proposals wrong, applied the wrong evaluation criteria, or ran an unfair competition — that is a bid protest, and it lives on a separate track. If your complaint is about the procurement itself rather than the winner's size, start with our guide on how to file a GAO bid protest instead.

Who can file a size protest

Under 13 CFR 121.1001, the people who can protest the size of an apparent winner on a set-aside include any offeror the contracting officer has not already eliminated from the competition for a procurement-related reason — such as being non-responsive, technically unacceptable, or outside the competitive range. In plain terms: if you were knocked out of the running for an unrelated reason, you generally cannot protest, because you are no longer an interested party. The contracting officer and the SBA can also initiate a size protest on their own, and when they do, the filing deadlines below do not bind them.

That "interested party" limit matters. The regulation specifically says a firm that has itself been found to be other than small for the procurement is not an interested party — unless it would be the only offeror left standing after the other firm is knocked out. So before you reach for a protest, it is worth confirming you are actually in a position to benefit if it succeeds.

The deadline: five business days, and it is unforgiving

This is the part that costs businesses their chance. Per 13 CFR 121.1004, a size protest must be received by the contracting officer before the close of business on the fifth day — excluding Saturdays, Sundays, and legal holidays — after the triggering event. The triggering event depends on how the contract was bought:

• Negotiated procurements (most RFPs): the clock starts when the contracting officer notifies you of the identity of the apparent successful offeror.
• Sealed bids: the clock starts at bid opening, where the apparent low bidder is known on the spot.

A few details are easy to miss and expensive to get wrong. The protest is filed with the contracting officer, not mailed to an SBA office — the CO then forwards it to the SBA. The deadline is about receipt, not postmark, so a protest that arrives on day six is late even if you sent it on day four. A protest filed too early — before bid opening or before you have been notified of the apparent winner — is dismissed as premature. And while the SBA will still forward a late protest to its files, the regulation is blunt: untimely protests are dismissed. There is no good-cause exception for a business that simply missed the window.

Because the window is so short, the practical move is to decide in advance whether you would protest if you lost, and to have your facts lined up before the award notice ever lands. Waiting until you get the bad news to start researching the competitor is how the five days evaporate.

What to put in the protest — and why specifics win

A size protest is not a hunch. The SBA weighs the record, and under 13 CFR 121.1009 it gives greater weight to specific, signed, factual evidence than to general, unsupported allegations or opinions. A protest that says "we think they're too big" gives the SBA nothing to act on. A protest that says "the awardee shares ownership, office space, and a managing officer with [named larger company], which makes them affiliated under SBA's rules, so their combined receipts exceed the size standard for the solicitation's NAICS code" gives the SBA a concrete thing to investigate.

Build your protest around the actual basis for ineligibility. The common grounds are:

• Affiliation. The awardee is controlled by, or under common control with, a larger business — through ownership, shared management, economic dependence, family relationships, or a joint venture — and the combined size exceeds the standard.
• Exceeding the size standard directly. The firm's own three-year average receipts (or employee count, depending on the NAICS code) are over the limit for the assigned code.
• Misrepresentation of status. The firm self-certified as small when it had already outgrown the standard.

Which size standard applies turns entirely on the NAICS code the contracting officer assigned to the solicitation, so make sure you are measuring against the right one — our guides on choosing NAICS codes and how to check an SBA size standard walk through how those numbers are set. If you are new to how set-asides are structured in the first place, small business set-aside types explained is a useful primer.

What happens after you file

Once the SBA receives a timely protest, the process moves fast and puts the pressure on the firm being challenged, not on you. Under 13 CFR 121.1008, the SBA's Area Office notifies the contracting officer, the protested company, and you that the protest was received, and it sends the protested company an SBA Form 355 — the questionnaire used to establish size — by certified mail or a delivery service that proves receipt.

From there, the burden shifts. The protested firm must return the completed Form 355 and all requested information within three working days of receiving the blank form. If it fails to respond, the SBA may presume that the missing information would have shown the firm is not small — a strong incentive to cooperate. And throughout, under 13 CFR 121.1009(c), it is the protested concern — not you, the protester — that carries the burden of establishing that it qualifies as a small business.

The SBA's Area Office then issues a formal size determination, generally within 15 business days where possible. The consequences for the awardee are real: if the SBA finds the firm is not small, the contracting officer cannot award it the set-aside contract, and a firm found other than small must update its size status in SAM.gov within two days of a final determination. One thing a size protest does not do is hand you the contract — if the apparent winner is disqualified, the award goes to the next eligible offeror in line, which may or may not be you. That is exactly why the "are you an interested party" question earlier matters.

If you lose — or win — you can appeal

A formal size determination is not necessarily the last word. Either side can appeal it to the SBA's Office of Hearings and Appeals (OHA). Per 13 CFR 134.304, a size appeal must be filed within 15 calendar days after receipt of the formal size determination — note that this deadline is in calendar days, unlike the business-day clock on the original protest — and an untimely appeal is dismissed.

The standard on appeal is demanding. Under 13 CFR 134.314, OHA reviews whether the size determination "was based on clear error of fact or law," and the appellant carries the burden of proof by a preponderance of the evidence. OHA is not a fresh do-over where you get to add the evidence you wish you had submitted the first time; it is a review of whether the Area Office got it wrong on the record it had. That reinforces the earlier point one more time: the quality of the original protest — and the documentation behind it — largely determines how this ends.

Should you file? A quick gut-check

A size protest is a legitimate, powerful tool, and it exists precisely because self-certification runs on the honor system and sometimes the honor system fails. But it is not free of cost — it takes your time, it can strain a relationship if the other firm is a potential teaming partner, and winning only helps you if you are genuinely next in line. Before you file, it is worth asking three questions: Do I have specific, documentable facts, not just suspicion? Am I an interested party who would actually benefit? And can I get a complete protest to the contracting officer inside five business days? If the answer to all three is yes, a well-built protest can reset an award that should not have gone where it did.

If you are weighing whether a particular loss is worth challenging — or you simply want a second set of eyes on a solicitation before you bid so you are not in this spot to begin with — WedgeBid can help. Our bid-response service covers solicitation review and response strategy, and the free Access Audit maps which federal, state, and city opportunities are realistically worth your time. You can also see where everything stands on our pricing page.

Not legal advice — see our disclosures for full disclaimers.