An SMTP server name is the hostname or domain address of the mail server responsible for sending outgoing email using the Simple Mail Transfer Protocol (SMTP). It tells your email client, website, or application exactly where to connect when it needs to deliver a message. Common examples include smtp.gmail.com, smtp.office365.com, or mail.yourdomain.com.

Now let’s break this down using the PAS copywriting framework—Problem, Agitate, Solution—so you not only understand what an SMTP server name is, but also why it matters for your business, website, or email system.

 

The Problem: Emails Don’t Send — and No One Knows Why

• You set up your email client.
• You configure your website contact form.
• You install an SMTP plugin.
• You click Send.

Nothing happens.

Or worse—you see:

• Authentication failed
• Could not connect to SMTP host
• Relay access denied
• Connection timeout

In most cases, the issue comes down to one small but critical setting:

The SMTP server name.

If this value is wrong—even by one character—your system cannot find the mail server responsible for sending email.

And without email, business stops.

• Customers don’t receive invoices
• Password reset emails fail
• Order confirmations disappear
• Support requests never arrive

Email is infrastructure. When it breaks, all downstream breaks with it.

What Exactly Is an SMTP Server Name?

An SMTP server name is the fully qualified domain name (FQDN) of the outgoing mail server.

It-typically looks like this:

• smtp.gmail.com
• smtp.office365.com
• mail.yourdomain.com
• smtp.sendgrid.net

It performs one function:

It tells your application where to connect to send mail.

When your system sends an email, it does not magically reach the recipient. It must:

1. Look up the SMTP server name via DNS.
2. Resolve it to an IP address.
3. Open a TCP connection (usually on port 587).
4. Authenticate.
5. Transfer the message.

Without a valid SMTP server name, that entire chain fails.

Read More: What Is an SMTP Server Name?