Embodiments of the invention relate to implementing run-time instrumentation sampling in transactional-execution mode. An aspect of the invention includes determining, by a processor, that the processor is configured to execute instructions of an instruction stream in a transactional-execution mode, the instructions defining a transaction. Completion of storage operations of the instructions is interlocked to prevent instruction-directed storage until completion of the transaction. A sample point is recognized during execution of the instructions while in the transactional-execution mode. Run-time-instrumentation-directed storing is performed, upon successful completion of the transaction, run-time instrumentation information obtained at the sample point.