What port do you send an email to on the company SMTP server?

What port do you send an email to on the company SMTP server?

• A. 10
• B. 25
• C. 110
• D. 135

Answer: (B)

Email delivery relies on the SMTP protocol, and SMTP servers listen on a well-known port for mail submission and relaying. The standard port to send an email to an SMTP server is port 25. This is the default channel used for SMTP traffic between mail servers and for clients relaying outbound mail in many setups. In many modern configurations, client submissions may use port 587 with encryption, but historically and commonly, reaching the SMTP server to send mail targets port 25. The other options correspond to different services (110 is for POP3 to retrieve mail, 135 is used for Windows RPC, and 10 is not a standard email port), so port 25 is the correct choice for sending to the SMTP server.

Email delivery relies on the SMTP protocol, and SMTP servers listen on a well-known port for mail submission and relaying. The standard port to send an email to an SMTP server is port 25. This is the default channel used for SMTP traffic between mail servers and for clients relaying outbound mail in many setups. In many modern configurations, client submissions may use port 587 with encryption, but historically and commonly, reaching the SMTP server to send mail targets port 25. The other options correspond to different services (110 is for POP3 to retrieve mail, 135 is used for Windows RPC, and 10 is not a standard email port), so port 25 is the correct choice for sending to the SMTP server.