To find out which SMTP server is being used, check the outgoing mail server settings in your email client or examine the email message headers. The SMTP server is typically listed as the “Outgoing Mail Server (SMTP)” in account settings, and in email headers, it appears in the “Received” lines showing the sending mail server. By reviewing these areas, you can quickly identify the SMTP server responsible for sending emails.
Now let’s explore this in detail — whether you’re troubleshooting email issues, auditing a mail system, configuring a website, or verifying email authentication.
What Is an SMTP Server?
SMTP (Simple Mail Transfer Protocol) is the technology responsible for sending email messages across the Internet. Whenever you send an email, your device connects to an SMTP server, which then transfers the message to the recipient’s mail server.
Common examples include:
- Gmail → smtp.gmail.com
- Outlook → smtp.office365.com
- Hosting providers → mail.yourdomain.com
For example, if you’re using Gmail, your outgoing server is usually smtp.gmail.com. If you’re using Microsoft Outlook with Microsoft 365, the SMTP server is typically smtp.office365.com.
