Connect in minutes!Deliver in seconds!Retain your customers!

Reliable and fast transactional email delivery

Easy set up, inbox placement and fast delivery at an extremely affordable price. ZeptoMail is a secure email service that is optimized to deliver your all-important transactional emails reliably.

 Watch demo






Reliable and fast delivery transactional emails

Delivery Time






Above data is the average of last 24 hours and updated every 5 minutes

ZeptoMail is powered by the creators of
Zoho Mail
—a platform with decade long experience in email hosting


"ZeptoMail's SMTP configuration option along with separate Mail Agents for specific functions and mail monitoring convinced us to move. We were able to migrate effortlessly from our previous solution. It has allowed us to minimize the frequency of transactional reports and helped us improve our business deals with better email deliverability."

Perathuselvam S

Deputy Manager - System Support India cements

"We were looking for a solution which is cost effective, easy to configure, has better analytics and customer support. ZeptoMail helps in improving customer relationship since it has high open rate. We can extract detailed report on deliverability. API integration is an excellent feature. It has been very good and more than 99% of the emails get delivered."

Vishal PS

VP | Product Head - CRMIIFL

"‌We have over 5 lakh traders. On a daily basis we send transactional emails in large volumes for daily reports, billing, digitally signed reports, retention statements etc. We tried multiple well-known services but were not satisfied with their pricing and performance. ZeptoMail's SMTP has helped us achieve affordable and reliable delivery."


IT HeadAlice Blue India

Testimonial UNB solutions 

Purnendu Mohanty

Founder / UNB Solutions

Read more customer stories

Integrate in

Finish the set up and start sending emails in just a few minutes. Choose between SMTP, email API, and plug-ins to get started—seamlessly.

SMTP configuration

Get started in seconds using our SMTP configuration. Connecting your existing application with ZeptoMail is as simple as entering our server details and your SMTP credentials.

Robust Email APIs

Use our robust email API library for a deeper integration. With a wide variety of API libraries to choose from, integration with ZeptoMail is easy and hassle-free.


curl "" \
-H "Accept: application/json" \
-H "Content-Type: application/json" \
-H "Authorization: [Authorization key]"  \
-d '{
"from": {"address": ""},
"to": [{
    "email_address": {
        "address": "",
        "name": "Receiver"
"subject":"Test Email",
"htmlbody":" Test email sent successfully. "}'      


// For ES6
import { SendMailClient } from "zeptomail";

// For CommonJS
// var { SendMailClient } = require("zeptomail");

const url = "";
const token = "[Authorization key]";

let client = new SendMailClient({ url, token });

  from: {
      address: "",
      name: "noreply"
  to: [
      email_address: {
          address: "",
          name: "Receiver"
  subject: "Test Email",
  htmlbody: " Test email sent successfully.",
  .then((resp) => console.log("success"))
  .catch((error) => console.log("error"));

using System;
using System.Net;
using System.Text;
using System.IO;
using System.Net.Http;
using Newtonsoft.Json;
using Newtonsoft.Json.Linq;

namespace Rextester {
  public class Program {
  public static void Main(string[] args) {
  System.Net.ServicePointManager.SecurityProtocol = 
  var baseAddress = "";
  var http = (HttpWebRequest)WebRequest.Create(new Uri(baseAddress));
  http.Accept = "application/json";
  http.ContentType = "application/json";
  http.Method = "POST";
  http.PreAuthenticate = true;
  http.Headers.Add("Authorization", "[Authorization key]");
  JObject parsedContent = JObject.Parse("{"+
    "'from': {'address': ''},"+
    "'to': [{'email_address': {"+
    "'address': '',"+
    "'name': 'Receiver'"+
    "'subject':'Test Email',"+
    "'htmlbody':' Test email sent successfully.'"+
  ASCIIEncoding encoding = new ASCIIEncoding();
  Byte[] bytes = encoding.GetBytes(parsedContent.ToString());
  Stream newStream = http.GetRequestStream();
  newStream.Write(bytes, 0, bytes.Length);
  var response = http.GetResponse();
  var stream = response.GetResponseStream();
  var sr = new StreamReader(stream);
  var content = sr.ReadToEnd();

import requests

url = ""

payload = """{
    "from": { 
      "address": ""
    "to": [{
      "email_address": {
        "address": "",
        "name": "Receiver"
    "subject":"Test Email",
    "htmlbody":"Test email sent successfully."
headers = {
 'accept': "application/json",
 'content-type': "application/json",
 'authorization': "[Authorization key]",

response = requests.request("POST",url,data=payload,headers=headers)


$curl = curl_init();
curl_setopt_array($curl, array(
    CURLOPT_URL => "",
    "from": { "address": ""},
    "to": [
            "email_address": {
                "address": "",
                "name": "Receiver"
    "subject":"Test Email",
    "htmlbody":" Test email sent successfully. ",
    "accept: application/json",
    "authorization: [Authorization key]",
    "cache-control: no-cache",
    "content-type: application/json",

    $response = curl_exec($curl);
    $err = curl_error($curl);


    if ($err) {
        echo "cURL Error #:" . $err;
    } else {
        echo $response;


import org.json.JSONObject;

public class JavaSendapi {
  public static void main(String[] args) throws Exception {
  String postUrl = "";
  BufferedReader br = null;
  HttpURLConnection conn = null;
  String output = null;
  StringBuffer sb = new StringBuffer();
  try {
    URL url = new URL(postUrl);
    conn = (HttpURLConnection) url.openConnection();
    conn.setRequestProperty("Content-Type", "application/json");
    conn.setRequestProperty("Accept", "application/json");
    conn.setRequestProperty("Authorization", "[Authorization key]");
    JSONObject object = new JSONObject("{\n" +
    "  \"from\": {\n" +
    "    \"address\": \"\"\n" +
    "  },\n" +
    "  \"to\": [\n" +
    "    {\n" +
    "      \"email_address\": {\n" +
    "        \"address\": \"\",\n" +
    "        \"name\": \"Receiver\"\n" +
    "      }\n" +
    "    }\n" +
    "  ],\n" +
    "  \"subject\": \"Test Email\",\n" +
    "  \"htmlbody\": \" Test email sent successfully.\"\n" +
    OutputStream os = conn.getOutputStream();
    br = new BufferedReader(
    new InputStreamReader((conn.getInputStream()))
    while ((output = br.readLine()) != null) {
  } catch (Exception e) {
      br = new BufferedReader(
        new InputStreamReader((conn.getErrorStream()))
      while ((output = br.readLine()) != null) {
    } finally {
        try {
          if (br != null) {
        } catch (Exception e) {
        try {
          if (conn != null) {
        } catch (Exception e) {

Affordable pricing

Pay as you go pricing.
No monthly plans.

Estimate your cost

10000 mails

1 credit = 10,000 emails

*Each credit is valid up to 6 months from purchase

for 10000 transactional emails

See full pricingContact sales


1 credit = 10000 emails Each credit is valid for 6 months from purchase

Ready to get started?

Pay-as-you-go system allows you to buy and pay for credits as and when you need them.

Contact sales for pricing

Transactional Email

What are transactional emails?

Transactional emails act as an acknowledgement for transactions between your business and your user. These emails are automatically triggered by user actions on your website or in your application.


Alert emails




Welcome email


Alert emails




Welcome email


Marketing vs Transactional

Marketing emails are bulk emails that are sent with the intention of selling or promoting a product or service. Transactional emails are unique emails that convey important information. They can be of different types, such as account information, invoices, and more, depending on your business.


Why are they important?

Transactional emails are the most important emails for any business. With an 8X higher open rate than marketing emails, they help foster trust, build your reputation, and establish communication with users. When done right, they're key to customer retention.

ZeptoMail Feature

 DeliverabilityEmail SegmentsEmail InsightsReputationTemplates

Great deliverability for your emails

We do one thing and we do it well—transactional email delivery. With an exclusive focus on transactional emails, our email sending is optimized for good deliverability and fast delivery. Your users will no longer be left waiting for their verification or password reset emails.

Segment your emails

If you run multiple businesses, applications, or send different types of transactional emails, having them cluttered together can be chaotic. With ZeptoMail, you can segment emails into streams by using Mail Agents. Each group comes with its own analytics and credentials.

Segment your emails

Deeper insight into your emails

You can enable email tracking for the emails you send out to view recipient activity. You can then view detailed logs and reports of each email that's processed through your account. It helps to stay on top of your email performance and troubleshooting.

Deeper insight into your emails

Protect your sender reputation

Having too many bounces or spam complaints can affect the delivery of your transactional emails. The suppression list in ZeptoMail allows you to block sending and tracking for specific email addresses that cause bounces, so you can protect your reputation.

Protect your sender reputation

Readily available templates

Writing the same email repeatedly eats up time that could be spent building your business. ZeptoMail comes with email templates for common transactional emails. You can pick from the ones available, or create your own from scratch.

Readily available templates

Why choose

Exclusively transactional

Undivided focus on transactional email delivery ensures great inbox placement and delivery in seconds

Easy to use

User-friendly interface that makes connecting ZeptoMail to your business seamless

Unbelievably affordable

Flexible pay-as-you-go pricing without the burden of monthly plans and unused emails

Delivery for all volumes

Proof of scalability with more than 25k domains, 5k organizations and 50 Zoho apps using ZeptoMail

24/7 support

Round the clock access to technical assistance over chat, phone, and email for all things ZeptoMail

No gatekeeping

No hidden costs—all of ZeptoMail's features are available to all of our users irrespective of sending volume

Need more

Secure email platform

We handle your important emails with care. ZeptoMail has multiple layers of security and privacy measures in place to ensure that your data is always secure.


Credits purchased

Feature-rich interface

ZeptoMail is a feature-rich platform that makes managing transactional emails easy. These features help send, manage and monitor emails you send out.

Full features

ZeptoMail's integration with WordPress, Zapier, Zoho CRM, Zoho Flow and many other applications, make workflows across multiple applications hassle-free.

Learn more

Frequently asked questions

What is a transactional email service?

A transactional email service is built to deliver automated applications. These emails are triggered when a user completes an action on a website or application—for example, orders placed, password resets, and more.

How do you send a transactional email?

Transactional emails from ZeptoMail can be sent using SMTP or API. SMTP is a simple configuration that helps you get started faster, while APIs can be used for a more robust and in-depth integration with ZeptoMail.

How to authenticate a domain to improve email deliverability?

Domains can be authenticated using protocols, such as SPF, DKIM, DMARC, and CNAME. In the case of ZeptoMail, SPF and DKIM configurations are mandatory in order to add domains to the platform. These authentication methods also help protect your domain's reputation.

Does ZeptoMail provide dedicated IPs?

While a well-managed and shared IP address offers a higher chance of great deliverability, certain businesses with high email volume may require a dedicated IP. You can contact us to learn more about which option will serve your purposes better.

How does ZeptoMail's credit system work?

Credits function as units of payment for ZeptoMail. Each credit allows you to send 10,000 emails. You can buy multiple credits, or one credit at a time. All credits expire six months after purchase.

Why do I need a transactional email service?

Marketing emails run a risk of being marked as spam by users. When this occurs, the delivery of transactional emails sent from the same service, also takes a hit. A dedicated transactional email service can help ensure good deliverability and to protect your sender reputation.

How to choose the right transactional email service?

Transactional emails are critical, making picking the best transactional email service both important and tricky. With multiple providers on the market, here are some pointers on what to look for: Deliverability, reasonable pricing, ease of setup, analytics and good technical support.