Where is SMTP server?

An SMTP server is an essential component of the email architecture. It is responsible for routing and delivering email messages between senders and recipients across networks and servers. But where exactly is the SMTP server located in relation to a user’s email account setup?


Where is SMTP server?

Understanding SMTP Server Role in Email Delivery

The SMTP or Simple Mail Transfer Protocol server plays a key role in the email delivery process. Here is a quick overview:

  • When a user sends an email from their email client (Outlook, Gmail etc.), the message first reaches the outgoing mail server (SMTP server). This is located with the user’s email service provider (ESP).
  • The outgoing SMTP server then routes the email via the open internet to the receiving mail server (SMTP Server) of the email recipient.
  • The receiving SMTP server receives and stores the email in the recipient’s mailbox where it can be accessed via POP or IMAP protocols.

So in summary – the SMTP server is located on the sending and receiving ends with both parties’ Email Service Providers. It is the bridge facilitating email transport across internet networks.

Locating the Outgoing SMTP Server

When you are setting up an email client to send emails, you need to specify the SMTP server settings. This is the location of the outgoing SMTP Sever that will route your emails to recipients.

Here is how to find out where your outgoing SMTP server is located:

  • Web based email services – For services like Gmail, Yahoo, Outlook.com etc, the outgoing SMTP server is already defined on their servers. You don’t need to locate it when setting up email clients.
  • Domain Email Accounts – If you have an email account tied to a custom domain name managed by a hosting provider or your organization, the domain registrar or IT admin will provide SMTP server name, port, auth settings etc. to configure your email client. The SMTP server will be hosted with your email host or on your company server.

So in most common email configurations, the outgoing SMTP server will be located with your Email Service Provider whether a public web service or private server host.

Locating the Incoming SMTP Server

The incoming SMTP server is located with the mail host of the domain receiving your email. For example:

  • If you are sending an email to [email protected], the receiving SMTP server will be located on company.com’s email hosting or mail server infrastructure that manages the domain and email delivery.
  • When an email is sent to your @yourcompany.com account, it will be routed to your company mail server which also hosts the inbound SMTP server for the domain.

In summary, the incoming SMTP server is hosted by the recipient’s email domain host as part of their email infrastructure.

Main Takeaway Points

  • The SMTP server enables routing and transport of email messages between senders & recipients located across different networks and domains.
  • The outgoing SMTP server is located with your Email Service Provider. This routes your emails over the internet towards the recipient’s email domain.
  • The incoming SMTP server is located on the recipient’s email domain mail server. This receives and delivers your email to the user’s mailbox.

So while users only interact with their email client and account, the SMTP servers facilitates the behind-the-scenes communication between networks to enable universal email services.


In essence, the SMTP server provides interoperability in email services between different addresses, domains and hosting configurations. The average user may never need to find out where their SMTP server is located. But the behind-the-scenes functioning of SMTP ensures users can seamlessly send email to anyone with an address. As such, it is the bridge at both ends enabling cross-compatibility between otherwise siloed email landscapes.

Frequently Asked Questions on Where is SMTP Server

  1. Q: What does an SMTP server do in email?
    A: The SMTP or Simple Mail Transfer Protocol server facilitates the transport of email messages between the sender’s and recipient’s mail servers over the internet. It routes and relays your emails across networks. 
  2. Q: What is the difference between SMTP and POP3 or IMAP?
    A: SMTP works on routing and sending of email messages. POP3 and IMAP deal with accessing and downloading received emails to your local email inbox. 
  3. Q: Where is Gmail’s SMTP server located?
    A: For Gmail, the outbound SMTP server settings are pre-configured when you set up the account on your email client. Emails are routed through Google’s proprietary mail gateways. 
  4. Q: How do I find my SMTP server host name?
    A: For custom domain emails, your domain registrar or IT admin will provide the SMTP host name, port details and authentication settings to configure email clients. 
  5. Q: Can I use any SMTP server for my email?
    A: No, you can only use your email host’s designated SMTP server mapped to your account domain and credentials for sending emails. 
  6. Q: What port does SMTP use for email?
    A: SMTP servers primarily use port 25 for communication. But many also support secured connectivity over port 587 or 465 using Transport Layer Security (TLS) encryption. 
  7. Q: Where should my SMTP server be located?
    A: Preferably in proximity to your geographic location for efficiency. But as long as connectivity is reliable, the location does not matter fundamentally. 
  8. Q: What is the difference between internal and external SMTP servers?
    A: Internal SMTP servers are inside an organization’s network for intranet mail routing. External ones route mail through the internet between networks. 
  9. Q: Can I run my own SMTP server?
    A: Yes, you can run an SMTP mail server on-premise or hosted on cloud infrastructure through providers like AWS if you have the technical capability. 
  10. Q: How can I troubleshoot SMTP server problems?
    A: Start with server error logs if available. Check connectivity issues, authentication failures, blacklisting etc. Reach out for technical help if problem persists. 
  11. Q: Is the SMTP protocol outdated and unsafe?
    A: SMTP has legacy issues compared to modern alternatives. But updated versions have security improvements through encryption mechanisms like STARTTLS. 
  12. Q: What are some alternatives to SMTP servers?
    A: Proprietary alternatives like Sendgrid, Mailgun etc are gaining popularity. And new standards like JMAP are aiming to replace SMTP in the future. 
  13. Q: Should SMTP servers have anti-spam and security mechanisms?
    A: Absolutely. SMTP servers should deploy DMARC, DKIM email authentication method, spam filters, virus scans and other controls for safety.

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