There are two ways in which you will be able to send emails using TransMail service:

Email Sending with SMTP

What is SMTP?

SMTP or Simple Mail Transfer Protocol is the method by which any application can connect with an SMTP server to send emails. In-order to use TransMail SMTP servers, you will have to configure your application settings with TransMail's SMTP information.

If your application is already using any other email provider to send transactional emails, it is easier to migrate to TransMail by replacing the existing SMTP settings with TransMail's SMTP settings.

To connect to TransMail via SMTP method add the following details:

SMTP Configuration settings for TransMail 

  • Server name -
  • Port Number, Authentication - 465 (SSL), 587 (TLS)
  • Username - emailapikey (we also support applications that use the From address as the username)
  • Authorization - Password. Visit here to check your password


  • TransMail supports TLS v1.2 for SMTP.
  • While sending your email via SMTP, the bounce address added in your Mail Agent should be used. If you leave the bounce address field empty or configure it with an invalid bounce address, then TransMail will use its default bounce address while processing your email.
  • If your SMTP application is restricting longer passwords, then you can generate a shorter password. Shorter passwords are generally less secure. Click on Generate shorter password to get your shorter password.
  • When you generate a shorter password, your application can either use the From address as username value or you can generate the new Username value for the shorter password by clicking on username value.

Email Sending with API

Your application can use TransMail's REST API to make HTTP requests to send emails via TransMail. The HTTP POST request can be made to our send mail API endpoint with the JSON message attached to the body.

Authentication Headers

Application developers can authenticate API requests to TransMail by adding an authorization parameter as shown below in the header section. This is the Send Mail Token (a unique token for every Mail Agent) that you can generate in your TransMail account.

Authorization - zoho-enczapikey <space> <send mail token>. You can visit here to get your send mail token.

If API requests are made to TransMail without these headers, you will receive HTTP response "401 Unauthorised" error.

Mail Send API - JSON format

JSON messages are passed in the body of the HTTP POST request. You can go to API documentation section to view:


Before you get started it is important to know that TransMail is for sending transactional emails like welcome emailers, password resets emails, OTPs. We do not support sending of bulk emails or promotional emails like newsletters or marketing campaign emails. If you are looking for a bulk email provider, you can visit Zoho Campaigns.