Which phrase is used when a transmission is finished and a reply is expected?

The phrase used when a transmission is finished and a reply is expected is "Over." In air traffic control and other radio communications, "Over" indicates that the speaker has completed their message and is awaiting a response from the recipient. This terminology is crucial for ensuring clarity and efficiency in communication, allowing both parties to understand that the speaker expects feedback or acknowledgment before continuing the conversation.

In contrast, "Out" signifies that the transmission has concluded and no reply is anticipated, while "Confirm" is typically used to request verification of information rather than indicating a conclusion of a message. "End" does not have the same standard usage in radio communication protocols and may lead to confusion regarding whether a response is expected. Thus, "Over" is the term that accurately conveys both the end of communication and the expectation of a response.