If done right, email marketing can be a wonderful tool for any company. This is not only about convincing readers to click through, it’s more important get loyal customers. With every email sent we learn more about our customers, and the customers about the brand. Reaching your customers is a complex puzzle of tools, text, design and logistics. This blog is a summary of important tips and rules.

In order to deliver your messages to your customers you need to have a good digital reputation and a trustworthy relationship with your customers. If your Reputation is poor and you don’t handle Authentication, it will generate a high Bounce Rate, which will ensure that your messages wont reach anyone. The number of bounced emails is directly related to the quality of your Subscribers list and even when your messages are noted as delivered, they end up in a spam trap or folder. Your domain and IP could be blacklisted if there are complaints. Here are some useful tips on what to consider to improve your digital reputation.

What to do when:

Your e-mails are delivered but not received
Whenever email deliverability is in question, ask yourself:
– Do I have my SPF record set up properly and is it currently valid?
– Are the emails being delivered or are they bouncing?
– What type of recipients are they?

Sudden increase of bounces
A poor Reputation and Authentication generates a high Bounce Rate – Check if your not blacklisted
– Analyse your subscribers list or segment
– If above fails, check-up your service provider


An email sender reputation is a score that an Internet Service Provider (ISP) assigns to an organization that sends email. It’s a crucial component of your email deliverability. The higher the score, the more likely an ISP will deliver emails to the inboxes of recipients on their network.

There are two types of sender reputation:
IP Reputation: An IP address identifies you and your servers. Based on your (and your IP address) historic behavior, determines your IP reputation, as it indicates what kind of mail you’re likely to send.

Domain Reputation: Your domain reputation is based on your sending domain instead of your IP address. This means that your brand takes precedence when it comes to ISP filtering decisions

How well is your reputation?
There are many free online tools to see what your reputation is, for example:

A high bounce rate could indicate that your reputation is poor.


Bounce rate

An “email bounce” means that the email that you have sent is not delivered. The mail server sends the sender a message back to let the them know that the email address is unreachable. The percentage of bounced emails against your send email is called the bounce rate. The bounce rate gives important information about your receivers.

There are two types of bounces
soft bounce: A soft bounce is an email that has not been delivered to your recipient because of temporary reasons. It might occur because the email is too large, the inbox is full or the email server is down. The email service providers will retry to send the email a couple of times more.

hard bounce: A hard bounce is an email that is sent back due to permanent reasons. The reasons for this can be various. Most of the time, the recipient’s’ email address is invalid or no longer in use.

It is valid to constantly check up with your subscribers list to create a good reputation.


Subscribers list

Make your unsubscribe clear and easily visible and better yet, add a permission reminder message alongside it to remind people where they signed up or gave you permission and point them towards unsubscribing if they are no longer interested in receiving your emails.

Your subscription should be just as easy as your unsubscribe. When they fill in the subscription form, a typo is easily made. With a double opt-in you can double check if it is who he/she says to be. In email deliverability terms, low open rates are a clear signal to ISPs that your recipients are not engaged with you, your brand or your content.

Engagement-Based Sunsetting: Remove email address from your mailing list if they do not open or click a message in some period of time. This time period varies depending on factors like your industry and sending frequency.

– Manage expectations by being clear from the very beginning what types of emails you will send and how often.
– Send a welcome email to reiterate these expectations.
– Deliver relevant, targeted and timely email messages that meet expectations.
– If it is within your capabilities, offer a preference center on your website to give subscribers more control over the content and timing of your emails.


SPAM traps

We all know spam folders, but a trap !? Spam traps are usually email addresses that are created for non-communication, but rather to lure spam. These email addresses will typically only be published in a location hidden from view such that an automated email address harvester (used by spammers) can find the email address. Since no email is solicited by the owner of this “spam trap” email address, any email messages sent to this address are immediately considered unsolicited.

How to avoid spam traps and folders?
Use an official company from address
Avoid using spam filter flagging keywords & characters
Create a double opt-in
Don’t buy subscribers



Reputation monitoring is the key to maximum email deliverability. By closely monitoring your complaint rates, you can prevent delivery failures before they happen. Delivery to spam trap addresses, as well as high spam complaint rates, are the main reasons that your IP ends up on a blacklist. Check your stats with each campaign deployment and look for delivery dips and low engagement rates. If your on one of the blacklists it is very important that you take steps to get your IP removed from the list.

Feedback loops
A feedback loop is an inter-organizational system by which an ESP forwards complaints from their mailbox owners to the sender’s organization. These complaints are registered when a user clicks the “Report spam” button in their email client.While it might seem risky to open yourself up to such direct complaints, it is better to handle them right away than having to find out that you have been blacklisted later on.

The List-Unsubscribe header is an optional block of text that email publishers and marketers can include in the header part of their emails. Recipients do not see the header itself. Instead, they see an unsubscribe button that can be clicked when they would like to automatically stop future messages. Including a List-Unsubscribe header in your emails will reduce complaints, improve deliverability and improve the experience of your subscribers.

Check if you are blacklisted and by whom:

Register your domain in clients like Gmail. https://developers.google.com/gmail/markup/registering-with-google



Email authentication, or validation, is a collection of techniques aimed at providing verifiable information about the origin of email messages by validating the identities of any message transfer agents (MTA) who participated in transferring and possibly modifying a message. If the identity of the sender can’t be authenticated, ISPs may reject the message or put it through additional filters to determine whether it should be delivered or not.

Authentication can be realized with the setup of SPF and DKIM records in the Domain Name System (DNS). SMTP defines (basic) message transport, not the message content. Thus, it defines the mail envelope and its parameters, such as the envelope sender, but not the header (except trace information) nor the body of the message itself. SPF allows the receiver to check that an email claimed to have come from a specific domain that comes from an IP address authorized by that domain’s administrators. The SPF record is stored within a DNS database and is bundled with the DNS lookup information. SPF check DKIM DKIM (DomainKeys Identified Mail) is an email authentication technique that allows the receiver to check that an email was indeed sent and authorized by the owner of that domain. It works together with DMARC (and SPF). DKIM signature check

DMARC allows the specification of a policy for authenticated messages. It is built on top of two existing mechanisms, Sender Policy Framework (SPF) and DomainKeys Identified Mail (DKIM). It allows the administrative owner of a domain to publish a policy in their DNS records to specify which mechanism (DKIM, SPF or both) is employed when sending email from that domain. Read more about DMARC at https://www.dmarcanalyzer.com/blog/

TLS and its now-deprecated predecessor, SSL are cryptographic protocols designed to provide security when your message is in “transit” over a computer network. Several versions of the protocols find widespread use in applications such as web browsing, email, instant messaging, and voice over IP (VoIP). TLS uses Public Key Infrastructure (PKI) to encrypt messages from mail server to mail server. This encryption makes it more difficult for hackers to intercept and read messages. TLS also supports the use of digital certificates to authenticate the receiving servers. Authentication of sending servers is optional. This process verifies that the receivers (or senders) are who they say they are, which helps to prevent spoofing.




– Use your brand name in your @domain_mailaddress.nl
– Use different domains for different types of messages
– After three bounces, the record is opt-out
– Make un-, subscription simple and clear
– Avoid spam traps with a double opt-in
– Keep an eye on delivery rate before it is too late
– Avoid spam keywords and shortened URLs
– Create a good balance between text and graphics
– Valid HTML and styles readable for all devices
– Add a text version

Gmail Bulk Senders Guidelines
Gmail Postmaster tools


Email deliverability is a complex thing to get right on your own, dont be afraid to call in the help of IT specialist, developers and other email marketeers.