The role reverses
Most small businesses start as subcontractors, doing work under someone else's prime contract. Becoming the prime who hires subs instead flips the relationship, and with it, the responsibility. You now own the government's expectations for the entire scope, including the parts someone else actually performs.
Subcontracting plans, above a threshold
Large businesses awarded big contracts are generally required to submit a subcontracting plan describing how they will provide opportunities to small and socioeconomic businesses, but the specific dollar threshold and applicability rules shift and depend on contract size and type, so check the clause in your own contract rather than assuming a remembered number. Smaller prime contractors are often exempt from the formal plan requirement, but the underlying discipline, documenting who you use and why, is worth keeping even when it is not mandatory, because it is also just good subcontractor management.
Flow-down clauses carry your obligations downward
Many of the clauses in your prime contract are required to flow down into your subcontracts, meaning your sub is bound by some of the same government terms you are: labor standards, certain certifications, security requirements, depending on what applies. Writing your subcontract agreements without checking which clauses must flow down is a common gap, and it is the kind of thing a government audit or a dispute will surface at the worst possible time. Build a flow-down checklist from your own prime contract before you send out a single subcontract.
Picking subs who will not sink your CPARS
The government's contract is with you, not with your subcontractor, so a missed deadline or a quality problem on their end becomes a mark on your CPARS record, not theirs. Vet subs the way a customer would vet you: past performance, actual capacity to do the work, financial stability to deliver before they get paid. A sub with the lowest price and no track record is a discount you may end up paying for twice.
Pay your subs promptly, for the same reason
Just as the Prompt Payment Act shapes when the government pays you, your own subcontract terms should set clear, reasonable payment timing, and you should actually honor it. A subcontractor waiting on your payment is more likely to deprioritize your work, slip a deadline, or simply struggle to deliver, and all of that becomes visible to the government as your performance, not theirs. Treating your subs the way you wish primes had treated you is not just good ethics, it is direct protection for your own rating.