What Is Email Relay And How Does It Work?

Sending mails to clients or organizations might look simple – just write the content and press ‘Send,’ right? But, learning all the aspects of email marketing is challenging. The email world is full of tricky words like email relay, IMAP, MTA, SMTP, and others.

Setting up contact lists and creating your first newsletter are great starting spots, but if you’re looking to take the next step in your understanding of email marketing, then you should take a closer look at SMTP relays.

SMTP is known as Simple Mail Transfer Protocol, and it is the backend operation that helps you and your business send, receive, and relay messages between senders and receivers.

An SMTP relay module allows email to be transmitted through the internet, from one server to another, for delivery. But what is an email relay?

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What Is Email Relay?

Email relay is also known as SMTP relay, which is the process of transmitting an email message from one server to another. If SMTP is the protocol for delivering outgoing email, you can think of a mail relay to transfer an email from one mail server to another.

Now, let’s discuss how it works.

How Does Smtp Relay Work?

Let’s take an example. When you send out your latest campaign, ‘Adopt a Cute Little Puppy,’ your company’s SMTP server relays your email to the server owned by your recipient. But if you were to send that campaign to someone with your corresponding domain, there would be no ‘email relay,’ as your SMTP relay server wouldn’t need to give the email to another SMTP server.

There’s a bit more happening behind the scenes, but this should give you a general overview of how things work.

4 Ways SMTP Relay Helps Your Business

An SMTP relay was first launched in 1982 and still is an extensively used standard today. When it comes to sending emails to different domains, SMTP relay is the service that makes it happen.

Now, let’s discuss how an SMTP relay can help your business.

1. Increase In Email Deliverability

Email deliverability is the ability to deliver emails to subscriber’s inboxes. It is what some business marketers use to assess the likelihood of their email campaigns reaching their follower’s inboxes related to actual delivery-like ISPs, throttling, bounces, spam, and bulking.

Along with business, its customers also grow. As usual, email services put a sending cap per day to every user; using SMTP relay will give you the means to send unlimited numbers of outbound emails.

This helps you reach out more new customers while keeping in contact with your existing clients. SMTP relay software also prevents internet service providers (ISPs) and email service providers (ESPs) from identifying your messages as spam with a CAN-SPAM compliance tool.

2. Protection Of Your Mailing Reputation

Email relay uses advanced web addresses and servers that block spammers and other attackers. You can ensure that your email marketing credit remains the same, whatever email address or domain you use for email marketing.

3. Prevent Your IP From Getting Blacklisted

As your email address and domain’s reputation are preserved, your email-sending IP address’s reputation will also be protected. IP addresses can only be ostracized if an attacker has connected to a network through WiFi and ethernet and uses that connection to send malicious emails.

You shouldn’t give unknown users access to your business’s email account, domain, and internet connection.

4. Safety Against Malware And Attacks

Organizations need malware scanning and spam filtering abilities at the mail client and the mail system levels. Organizations should also direct awareness and training activities for users, including telecommuters, to better prepare to identify malicious mail messages and handle them well.

Even without receiving malicious emails, you won’t get to experience DDoS attacks because your SMTP will automatically block mail from anonymous email senders. This ensures you a continued email marketing progress without downtime.

So, these were the four steps in how SMTP relay can help your business. To implement email marketing in the right manner, you must consider your follower’s preferred content using a personalization and list segmentation tool. You should also use an email marketing platform feature called automation, where you can send your customer confirmation emails, certificates, and security automatically.


When we talk about open SMTP relays, we usually mean an outgoing server that accepts messages from other domains without requesting authentication. Your SMTP server can be used as a “link” between two different ones to communicate in simple words.

One of the biggest dilemmas with email relays is that spammers can use them to send bulk-free messages: if it happens to yours, your IP will be blacklisted, and you will never be able to send bulk emails from it.

That is why many internet companies limit the number of how many relays you can do per day – which is unfavorable for your email marketing strategy. To prevent such adverse circumstances, you can shift to a known SMTP service, which relies only on secured IPs and always ask for the user’s credentials to work.

If you are interested in even more technology-related articles and information from us here at Bit Rebels, then we have a lot to choose from.

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