FAR 9.104-4—Subcontractor responsibility.
Plain-English Summary
FAR 9.104-4 explains who is responsible for judging whether a prospective subcontractor is responsible and how that judgment can affect the prime contractor’s own responsibility determination. It covers the general rule that prospective prime contractors must evaluate their subcontractors, the special limitation that debarred, suspended, or otherwise ineligible firms cannot be used as subcontractors where the FAR restrictions apply, the Government’s ability to ask for written evidence of a subcontractor’s responsibility, and the contracting officer’s authority to make a direct responsibility determination for a subcontractor when the Government’s interest requires it. The section also identifies situations where direct Government review may be appropriate, such as medical supplies, urgent requirements, or substantial subcontracting. In practice, this means subcontractor vetting is usually a prime contractor duty, but the Government can step in when subcontractor performance is especially important to contract success or public interest. The rule matters because a weak or nonresponsible subcontractor can undermine the prime’s ability to perform and can influence whether the Government awards to the prime at all.
Key Rules
Prime vets subcontractors
As a general rule, prospective prime contractors are responsible for determining whether their prospective subcontractors are responsible. The Government normally relies on the prime’s judgment and due diligence rather than independently reviewing every subcontractor.
Suspended or debarred firms restricted
The rule is subject to FAR 9.405 and 9.405-2, which address debarred, suspended, and otherwise ineligible firms. A prime contractor must not ignore those exclusions when selecting subcontractors.
Subcontractor responsibility can affect prime responsibility
A subcontractor’s responsibility determination may influence the Government’s assessment of the prospective prime contractor’s responsibility. If the subcontractor is critical to performance and appears incapable, that can raise concerns about the prime’s overall ability to perform.
Written evidence may be required
The prospective contractor may be asked to provide written evidence showing that a proposed subcontractor is responsible. This can include documentation supporting the subcontractor’s capability, resources, experience, or performance record.
Government may determine subcontractor responsibility directly
When it is in the Government’s interest, the contracting officer may directly determine a prospective subcontractor’s responsibility. The regulation gives examples such as medical supplies, urgent requirements, or substantial subcontracting.
Same standards apply to subcontractors
If the Government makes the determination, it must use the same responsibility standards that apply to prime contractors. The subcontractor is not judged under a different or lower standard simply because it is not the prime.
Responsibilities
Prospective Prime Contractor
Evaluate the responsibility of proposed subcontractors, ensure they are not excluded under applicable debarment or suspension rules, and be prepared to provide written evidence supporting a subcontractor’s responsibility when requested.
Contracting Officer
Consider whether a subcontractor’s responsibility affects the prime contractor’s responsibility, request written evidence when needed, and directly determine subcontractor responsibility when the Government’s interest justifies doing so using the same standards applied to prime contractors.
Government/Agency
Use subcontractor responsibility information as part of the overall responsibility assessment of the prospective prime contractor and intervene directly in subcontractor responsibility determinations when the procurement circumstances warrant it.
Prospective Subcontractor
Demonstrate capability, integrity, financial and technical capacity, and other responsibility factors if its responsibility is questioned or if the Government or prime contractor requests supporting evidence.
Practical Implications
Prime contractors should treat subcontractor vetting as part of their own responsibility package, not as a separate afterthought, because a weak subcontractor can jeopardize award to the prime.
Contracting officers may focus on key subcontractors in high-risk procurements, especially where the subcontractor will perform a major share of the work or provide mission-critical items.
Documentation matters: primes should be ready to show why a subcontractor is responsible, particularly for specialized, urgent, or high-value subcontracting arrangements.
A common pitfall is assuming subcontractor issues are purely private matters between the prime and its subs; in some cases, they directly affect the Government’s award decision.
Another risk is overlooking exclusion status under FAR 9.405 and 9.405-2, which can create compliance problems and delay or derail the procurement.
Official Regulatory Text
(a) Generally, prospective prime contractors are responsible for determining the responsibility of their prospective subcontractors (but see 9.405 and 9.405-2 regarding debarred, ineligible, or suspended firms). Determinations of prospective subcontractor responsibility may affect the Government's determination of the prospective prime contractor's responsibility. A prospective contractor may be required to provide written evidence of a proposed subcontractor's responsibility. (b) When it is in the Government’s interest to do so, the contracting officer may directly determine a prospective subcontractor’s responsibility ( e.g., when the prospective contract involves medical supplies, urgent requirements, or substantial subcontracting). In this case, the same standards used to determine a prime contractor’s responsibility shall be used by the Government to determine subcontractor responsibility.