What are transactional emails?

Transactional emails are automated, real-time messages sent between a sender and a recipient triggered by a specific action executed within an application or a website. They are a common and indispensable technique utilized by businesses worldwide to preserve customer relationships. They are usually sent programmatically either by using an email API or SMTP server.

Why are transactional emails so important?

Transactional emails are a great opportunity for you to build superb customer relationships. Not only are they automated, which avoids any manual input, but they also have particularly high open rates and click-through rates, since customers expect their arrival. Sending a well-timed email that confirms a successful transaction made by your customer helps to boost their trust in you and therefore promotes a long term relationship. Always remember: a happy customer is a long-term customer.

Different types of transactional email:

There’s just so many types

Welcome emails

Welcome emails are believed to be one of the most crucial types of transactional emails out there. Being that these are the very first impressions you are making on your customers after signing up to your service or product, they have a considerable amount of influence on the interactions going forward. You can learn more about welcome emails and how to write the ultimate one in our post: Welcome emails: 8 best practices to follow.

Receipt emails

E-receipts are sent to customers following a transaction and contain information relevant to it. Having high open-rates, e-receipts have significant potential to improve customer relations and increase revenue, establishing reliability and a sense of security. You can learn more about receipt emails and how to write the best one for your business in our post: Receipt emails: 7 best practices to follow.

Dunning emails

Dunning emails are account-related messages sent to remind customers about failed payments, card expirations, or overdue invoices. While these aren’t a joy to send out or receive, they are a necessity for any business, since customers must be aware of any billing issues they might be having. You can learn more about dunning emails in our post: Dunning email: 9 best practices to follow.

Password reset emails

With all of the passwords we are expected to remember, forgetting one happens all the time. This makes password reset emails quite the popular type of transactional email. Since customers can’t access their accounts without a password, they will be anticipating the immediate arrival of a password reset email. You can learn more about password emails and how to write a great one in our post: Password reset email: 7 best practices to follow.

Feedback request emails

Feedback request emails can be an excellent way to help create a positive customer experience, help keep businesses on course, and shed light on how others perceive their performance. The end goal is to obtain an honest response from customers regarding their experience with your service/product. You can learn more about the importance of feedback request emails and how to write a remarkable one in our post: How to write a winning feedback request email: 8 best practices to follow.

Renewal emails

Renewal emails are sent to customers in order to remind them that their subscription, contract, or membership is about to expire. Renewal emails are crucial to customer retention and loyalty. The customer should feel as though they are being thought of and their business is valuable, to both parties of course. You can learn more about renewal emails in our post: Renewal email: 6 best practices to follow.

Referral emails

Loyal customers are your best advocates. Referral emails are a great way for organizations and companies to spread the word about their products using the help of established, satisfied customers. Those kinds of emails usually offer referrers a variety of incentives to encourage them to get new customers on board.

Transactional email best practices:

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Follow these guidelines to send the best transactional emails

Part 1: Meta data

Email metadata is the information that appears in the header of an email for the purpose of simplifying the sorting and identification process by highlighting attributes of the data it describes. It contains information such as the subject, date, sender’s address, and receiver’s address. An email’s metadata forms the first impression the recipient will have of your business and has a direct impact on whether the customer will even open the email or not.

Email Authentication

Taking the proper steps when it comes to email authentication is necessary in order to avoid malicious spam/phishing attempts and improve your delivery rates. Email authentication is the process of validating an email’s authenticity through a set of security systems composed of three main email authentication protocols: DKIM, SPF, and DMARC. The purpose of the security system is to make sure that the email message came from the claimed sender and wasn’t forged somewhere along its way to the coveted inbox.

DKIM - (DomainKeys Identified Mail) is an email security protocol that provides a way to confirm a domain name identity that is associated with a message by using cryptographic authentication. You can read more about DKIM in our post: Email authentication methods Part #1: What is DKIM?.

SPF - much like sunblock, this SPF (Sender Policy Framework) also protects. It is an email authentication technique aimed to assist the receiving server in detecting forged sender addresses. It does so by cross checking a DNS record that lists email servers that are permitted to send email on behalf of your domain. You can read more about SPF in our post: Email authentication methods Part #2: What is SPF?.

DMARC - (Domain-based Message Authentication, Reporting, and Conformance) is an email authentication standard made to protect both email senders and recipients from attackers who send spam and phishing email by spoofing a domain. You can read more about DMARC in our post: Email authentication methods Part #3: What is DMARC?

From & reply-to addresses

The first thing recipients see within an email is who sent it. Your email address should match your brand name so that the recipient will not question its authenticity. In addition, the email signer at the end of the message should also be the sender. Most importantly, you should not send your emails from a no-reply address because this may frustrate your customers and create a lack of communication if they do happen to have questions or require further assistance. Besides, you’d actually be glad to hear back from them.

Subject line

Adding relevant information in your subject line will increase the chances that recipients will open your email. A transactional email’s subject line must notify customers on what the email is about and why they should open it. Stay away from misleading subject lines that can easily confuse the recipient, or even get your email marked as spam.


A pre-header is that brief text that appears after the subject line when displaying an email in the inbox. This text gives recipients a slight hint regarding the content of the email prior to opening it. A good preheader can encourage recipients to either open your email or ignore it, so be as straightforward and relevant to your content as possible.


Including all recipients in the main To field of an email might be the easiest way to go, but it’s not necessarily the right one. The To and Cc fields can be used to filter and organize emails, so if you want to make things simpler for your customers, you should insert the primary recipients in the To field and any other recipients should be added in the Cc field.

Setup Gmail inbox actions

Gmail inbox actions allow users to interact with your service right inside the Gmail platform. They are a great way to improve your transactional emails and give them even more use. These Actions can make life easier for your users by enabling them to perform actions, such as resetting passwords or leaving a review, without even having to open the email.

Part 2: Design and content

Use a responsive design

Responsive email design is all about creating customized content for your user's chosen device. While your transactional email can look outstanding on a laptop, it may be a complete mess when opened on a small mobile screen. Make sure that your transactional emails are optimized for desktops and mobile devices alike so that customers will be able to open and read them on the device of their choosing. Your design has to be proportioned correctly to fit a mobile screen, and resized accordingly when opened on a desktop.

Use plain text + HTML

When sending transactional emails, you should always aim to increase the chances of your email reaching its destination. HTML-only emails don’t often pass spam filters, which is why it’s recommended to include both HTML and plain text when sending transactional emails. Keep in mind that the plain text version’s content should be similar to the HTML one, so that it won’t give spam filters any reasons to raise red flags.

Make it personal

Make your customers feel valued and unique, starting with a personalized greeting. Emails that have the customer's name in them are much more likely to be read. Additionally, if you happen to have some extra information about this customer from the sign up page, you can use it to improve the email and provide the user with information that’s specifically interesting for them. Furthermore, keep track of your user’s activity and only send them emails that are relevant. For example, don’t send a feedback request email to a user that has yet to use your application, but rather something more along the lines of “Need help getting started?”.

Use absolute times

When including dates and times in your email, don’t use shorthand versions for relative times. There is no telling when your email will be opened (some lucky people do go on vacations from time to time) so it’s best to mention absolute times instead of “only today”.

Explain why users received this transactional email

The purpose of the transactional email you’re sending is not always obvious to your customers. While Welcome or receipt emails are expected, there are some cases in which your customers might get confused as to why they are receiving them so be sure to clarify. For example, when sending a feedback request email, you can write something like “As part of our efforts to improve our customer offering, we would like to get your view on what works for you and what doesn't within our platform by answering a few questions”.

Allow notification management

It's true that all of your transactional emails have a purpose, but some of your customers might not want to receive each and every one of your updates. Help those customers maintain an organized inbox by allowing them to easily manage their notification preferences.

Choose a trustworthy email service provider

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