How an SMTP relay service works (and why you should use a professional email relay for your sends).

Sending and receiving emails is far from a simple process. A professional SMTP relay service enables you to smoothly send bulk emails, safeguarding your sender reputation and enhancing your deliverability.

An SMTP (Simple Mail Transfer Protocol) relay is a service that facilitates the transmission of emails from one mail server to another, acting as a virtual mail carrier that ensures messages are delivered to their respective recipients.

If you don’t use an SMTP relay service for sending your emails, you can still utilize the SMTP relay of your email server. However, by doing so, you might end up sharing your IP address with spammers, which could harm your sender reputation.

In simpler terms, this means your emails might not reach their intended destinations due to deliverability issues. But you can address this problem by employing a professional SMTP relay.

Let’s explore how.

How does an SMTP relay actually work?

How does an SMTP relay work

To begin with, without an SMTP relay, you wouldn’t be able to send email messages to anyone outside of your domain (which is obviously a problem).

Every time you click the Send button, an SMTP connection is established. Your server starts communicating with the recipient’s SMTP server, using a series of SMTP commands or short phrases. These commands transfer data that authenticate each phase of the sending process.

The SMTP client sends your email address, the recipient’s email address, and the content of your message. If everything is in order, your emails are sent.

5 benefits of a professional SMTP relay service: here’s how it can enhance your email sending.

When you send an email message, there are three main factors that influence your ability to land in the main inbox:

  • your SMTP infrastructure;
  • the sender reputation;
  • your message content.

Adhering to the last point doesn’t require you to be particularly adept: generally, you should avoid using spam words in the content and in the subject of your message. Additionally, strive to maintain a text free from typos. 

Of course, your message must be devoid of ambiguity and should not contain scams or similar content.


And what about the other two points? Well, your SMTP infrastructure and the reputation of your domain and SMTP can also give you quite a headache. To manage these aspects personally, you should regularly monitor, diagnose, and resolve delivery issues, so you can build a good sender reputation.

But we know it: not everyone has the time or expertise to do so. 

And that’s why companies turn to SMTP relay services: to enhance their deliverability and reputation without worrying about technical aspects or compromising their sending capability.

But let’s explore together 5 of the advantages that an SMTP relay provider can offer you.

1. An SMTP relay provider offers you the sending infrastructure.

Internet Service Providers (ISPs) assess the reputation of your domain and IP address to determine whether your emails will reach recipients’ inboxes or end up in the spam folder.

A smart host SMTP service adds your company’s domain to the list of trusted senders, thus safeguarding the reputation of your IP address.

2. SMTP relays enable businesses to send large quantities of emails.

Many ISPs and webmail providers impose sending limits to prevent spam and other scams. This is because these services are designed for one-to-one communication rather than mass sends (such as email marketing campaigns or transactional emails). This can restrict your company’s ability to nurture, engage, and support your customer base.

But here’s the good news: SMTP relay services allow you to send substantial volumes of emails without encountering sending restrictions.

3. SMTP relay services provide expert technical support.

SMTP relay service providers like turboSMTP specialize in email delivery, monitoring, and enhancement of sending practices. With an SMTP relay provider like turboSMTP, you can access top-notch email infrastructure and have an expert support team at your disposal to help you resolve even complex issues.

4. SMTP relay services provide you with detailed metrics and statistics.

A public SMTP relay, such as the one provided by your ISP, doesn’t allow you to track your campaign data. For instance, you won’t know if your subscribers are receiving the emails you send, and you won’t be aware if your messages are flagged as spam or resulting in bounces.

On the other hand, a professional SMTP relay server like turboSMTP enables you to monitor your sends, including bounces, spam reports, opens, clicks, and more.

SMTP relay service statistics

In other words, SMTP services provide crucial data and insights, allowing you to understand when your emails are successfully delivered and when they don’t reach their intended recipients at all.

5. An SMTP relay provides an intuitive interface, allowing you to save time (and energy).

SMTP relay service dashboard

Unlike a self-managed server, most SMTP relay services offer a clean and user-friendly interface that’s ready to use. A better UI makes it easy for anyone in your organization to find, highlight, and understand email information.

How can TurboSMTP’s SMTP relay service help you enhance your outcomes?

TurboSMTP offers you an SMTP relay service that can assist in improving the outcomes of your bulk email sends. Here are some of the key benefits:

TurboSMTP's relay service enhances the performance of your email system

TurboSMTP’s relay service enhances the performance of your email system

When a message is transmitted, the server you use must connect to the recipient’s server to facilitate delivery. Consequently, when you send emails to multiple recipients, your server needs to establish separate connections with each recipient’s server. Employing an SMTP relay service enables you to optimize the performance of your email system by providing a single delivery point to establish connections with.

An SMTP relay service to enhance security through email authentication

An SMTP relay service to enhance security through email authentication

TurboSMTP implements email authentication to bolster the security of transmitted messages. By doing so, it ensures that only authorized senders can communicate through your IP address. This approach significantly improves both the delivery rate and overall security of the server.

In simple terms, this translates to a higher likelihood of your emails reaching their final destination securely and reliably.

A professional relay service for monitoring reports and statistics

A professional relay service for monitoring reports and statistics

TurboSMTP provides you the opportunity to access and monitor statistics and reports related to your emails. You can analyze open rates, delivery rates, bounce frequency, and obtain other detailed insights in a simple and intuitive manner.

Our customer support speaks your language

Our customer support speaks your language

By choosing turboSMTP you not only have an effective SMTP relay provider, but also a customer support service available in your language whenever you need it.

Our customer support team will always be ready to address any issues you may encounter and solve them in the best possible way.

An SMTP relay provider to keep your contact list clean

An SMTP relay provider to keep your contact list clean

Emails that are not delivered can have a negative impact on your business. Whenever a message you send does not reach the recipient’s inbox, the recipient’s address is placed on an exclusion list. As a result, this specific address will no longer be a recipient of your e-mails.

Thanks to turboSMTP you can keep your contact list in an optimal state by only including addresses that can actually receive and interact with your messages.

A secure sender address thanks to domain records

A secure sender address thanks to domain records

TurboSMTP service provides complete protection for you and the recipients of your e-mails, effectively preventing spam, phishing and spoofing attempts through its e-mail authentication mechanism. This approach is based on a set of multiple methods to establish your authenticity as a legitimate and trustworthy sender in the eyes of email services.

A customised tracking domain to monitor email opens and clicks

A customised tracking domain to monitor email opens and clicks

A Custom Tracking Domain is a domain that you exclusively use to track email opens and clicks.

Through TurboSMTP’s Custom Tracking Domain service, you will be able to keep your reputation as a sender intact, enhance your email delivery capacity and improve engagement rates with your content.

Discover all the benefits of our SMTP relay service: try turboSMTP now.

In any business environment, the adoption of an SMTP relay service is crucial for both internal and external communications. A professional relay service offers numerous benefits, including improved online reputation and increased deliverability.

This allows you to protect the integrity of your domain, preventing anyone from impersonating you or a member of your staff. It also allows you to track the path of your emails and user actions.



  1. Introduction
  2. How does an SMTP relay work
  3. 5 benefits of a professional SMTP relay service
  4. How can TurboSMTP’s SMTP relay service help you enhance your outcomes
  5. Conclusions