How do you receive Invoice Emails in milliseconds ?

Ever thought how do you get your invoice so quickly as you order from Swiggy or Uber Eats?

Your emails may be generated from various sources like CRM, CMS, website, app or any other campaign management tool. You need to integrate these applications with a transactional email service or SMTP relay servers (ESP)

Setting up the system to send transactional emails is a one-time effort. It’s plain, simple and easy. It involves 3 steps:

STEP 1: Set up your DNS – The first step in setting up your transactional emails is to set up a domain from which you will send emails to your customers. One should carefully select this domain. It is recommended to select sub-domain of the main domain to send these emails and also ensure no marketing or triggered emails are sent from this domain, especially if your monthly email volumes are in millions.

Once you have the right domain ensure it is authenticated via SPF, DKIM, and DMARC.

SPF: This is permission given to sending servers by the domain. The domain owner can define IPs by going in TXT records of the domain. This will ensure that only those IPs have permission to send emails from this domain. It is one of the best practices and hence you’ll find 90% of industry does it.

DKIM: This is good to follow the authentication process where the email that is being sent is digitally signed by domain key. It is then decrypted by the recipient ISPs’ server, thus ensuring the content does not tamper on the way and is coming from a trusted source.

DMARC: Domain-based message authentication, reporting, and conformance are another validation that detects and prevents email spoofing. It reports any fraudulent email sent from your domain. This is very critical for transactional emails.

STEP 2: Get SMTP credentials – You can integrate your application via SMTP or API protocols. Your application will need the following details to integrate and start sending emails via SMTP protocol.

Username and Password of your SMTP key

Hostname eg in our case we provide

SMTP Port via which the connection happens – most used are 25, 2525 & 587.

Senders prefer sending emails using SMTP as it is the fastest and easiest way to start sending your emails.

STEP 3: Set content and start sending – Keep it simple, don’t load your email with HTML or many images and use images only where absolutely relevant and required. 3 rules – Don’t sell, don’t confuse and don’t overrate branding in these emails. Just keep it simple.

Now you’re ready folks, let’s start sending!

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