Which FAR clauses flow down to your subcontracts
Flow-down is the most misunderstood word in federal subcontracting. The clause itself, not a separate chart, is the authority, and the matrix shows you where to look.
A subcontract is a private contract, but a federal prime contract reaches into it through a small number of clauses that are written to flow down. The power to flow a clause down does not come from the prime contractor. It comes from the clause's own prescription, which directs the prime to include a stated flow-down in its subcontracts. That is why the honest answer to "which clauses flow down" is always: read the clause.
The matrix is still the right place to start. A clause that never appears in a contract-type column is generally not one that carries a flow-down obligation, because the flow-down clauses are the ones inserted into the prime contract in the first place. Filter the reference by your prime's contract type, and you have the candidate list. From there, open each clause in eCFR and look for the flow-down sentence, usually phrased as a requirement to insert the clause, or a stated substance of it, in subcontracts under the contract.
The flow-down rules are not uniform, and the differences are the whole point. Some clauses flow down only to subcontracts above a stated dollar threshold. Some flow down only when the subcontract is for a stated category of work. Some require the full clause, others only its substance, and others require a representation rather than a term. Several flow down only one level, so a lower-tier subcontract may be outside their reach. Treating the matrix as though every R meant "flow this down" will over-apply the flow-downs and put terms in your subcontracts that the government did not ask for.
A practical method that holds up: take the prime contract type from the matrix, list the required and as-prescribed clauses, then for each one open its eCFR section and capture the exact flow-down sentence and any threshold or category condition. Keep that one-page crosswalk with the subcontract file. If a dispute later turns on whether a clause should have flowed down, the crosswalk is the evidence, and it is defensible because every entry cites the regulation.
The commercial-items column is the shortcut worth knowing. When your prime is a commercial acquisition, a large body of clauses is incorporated by reference through 52.212-4 and 52.212-5 rather than inserted clause by clause, and the flow-down story runs through those. MyFCExperts marks the incorporated-by-reference column so you can see when the shortcut applies.