All businesses today recognize what a powerful tool email is to the value of their product or service. It is essential for contacting and building important relationships with customers, and while it may be a bit old-school (email has been around for about 50 years), email providers are constantly up to date when it comes to detecting spammers and preventing certain emails from reaching their destination. In sum, email subdomains are a vital part of getting your emails to land in your customers’ coveted inboxes and choosing the right one matters.

What are email subdomains?

Hold on, let’s not get ahead of ourselves! Before we begin talking about subdomains, we should get down to the basics and establish an understanding of domains.

Every email address contains a sender username and a sender domain. For the sake of this post, we’ll be using our lovely made up company “Blumiblum”, a cat dating app for cats of all kinds.

We met on Blumiblum

Blumiblum operator’s email address is (Bluma is my beautiful tricolor cat), the username is “bluma” and the domain is “”.

Domains are the unique, human-readable identifiers of services on the internet such as websites, ftp servers, email services, api endpoints, and many more. Domains are frequently referred to as “root domains” or “parent domains”, which are titles given to them because they can be accompanied by subdomains (often referred to as “child domains”), indicating that they are a subsection of a larger domain (the parent). For example: can have its very own “child”:

Why use an email subdomain?

Nowadays, email reputation is EVERYTHING! What is an email reputation, you ask? Well, It is essentially a score assigned to your organization (or domain) by the internet and email service providers after calculating different metrics such as sending volume over time, complaint rates, bounce rates, spam trap hits, message filtration rates, and more. The higher the reputation, the more likely it will be that your email will be delivered. So, what does that have to do with subdomains, exactly? Sender reputation is directly connected to the domain you are sending your email from. If you’re sending your newsletters from one subdomain and those subscribers who don’t remember signing up to your newsletter mark them as spam, this shouldn’t affect the sender reputation for the subdomain from which you’re sending operational or sales emails from. You can read more in depth about this subject in our blog post “Should I be using a subdomain to send email?”.

Which email subdomains should I use to send different types of email

You have now reached the fun examples part, yippee!

Remember - Choosing subdomain names is your job, so choose wisely! We recommend going for a safe and clear subdomain name that reflects the different types of emails’ goals, making it easy for your customers to recognize the purpose of your email.

Email newsletters

Newsletters are a vital part of any email marketing strategy. It’s a great way for businesses to establish and maintain a continuous relationship with their customers and keep them updated.

Some examples of subdomains that work well for Blumiblum’s newsletter are:, or, if you’re a real cool cat:

Automated/triggered emails

Automated emails are carefully planned messages businesses send to customers at scheduled times or in direct response to actions made on their website or web app. Some examples of automated emails are welcome emails, mid-trial reminders, and billing issues alerts.

Here are some subdomains that work well for automated emails from Blumiblum:,, or

Billing emails

It’s true, billing emails are also automated emails. However, they get a subdomain of their own since they are related to what some believe is the most important aspect of a business - money. Emails such as payment collection, late payments alerts, and credit card updates should get their own assigned domain. For example: and

Sales emails

Businesses utilize sales emails to introduce and promote products or services to customers. This is a popular approach when it comes to increasing revenue, attracting new customers, and strengthening relations with existing customers.

A subdomain for sales emails from Blumiblum’s may be:

Another effective method is to use the geo (eu, us for example) or hq (for headquarters), if your business is broken down to geography, in order to show customers that your email is specific to people such as them. Well, people from the same continent anyways! In any case, it’s a bit more personal and it’s a completely different subdomain to use. For example:

Support emails

Every business needs a support team, and every support team uses emails to assist their customers. Let's face it: no product or service is entirely perfect. When sending a support email, you want your customers to recognize that the purpose of the email is to provide them with a solution to their problem even before opening the email. This is why your support team should have their own subdomain, preferably something like: or to highlight their friendly and welcoming nature.

Day to day emails (to suppliers, customers)

We covered email newsletters, automated emails, billing emails, sales emails, and support emails, but what about your day to day correspondence with customers, suppliers and even your boss? You want to avoid sending your suppliers an email from a address, since they are not likely to open it. For this case, we recommend using a simple one like or not using a subdomain at all, but instead using your primary domain (i.e.

Mailer To Go is a simple, secure, and scalable automated email delivery service that allows you to send transactional emails. You can use Mailer To Go to send email from different domains and subdomains by adding your verified domain through a simple streamlined process. Find out more and give it a try now by clicking on this link to start sending those important emails!