Build SendGrid X-SMTPAPI headers in PHP.
PHP Shell

BuildStatus Latest Stable Version

This module helps build SendGrid's SMTP API headers.

Learn more about the SMTP API at SendGrid's documentation.


All updates to this module is documented in our CHANGELOG.



  • PHP version 5.6 or 7.0
  • The SendGrid service, starting at the free level

Install with Composer

The following recommended installation requires

Add the following to your composer.json file.

    "minimum-stability" : "dev",
    "require": {
        "sendgrid/smtpapi": "~0.5"

Then at the top of your script require the autoloader:

require 'vendor/autoload.php';

Alternative: Install from zip

If you are not using Composer, simply download and install the latest packaged release of the library as a zip.

Then require the library from package:


Previous versions of the library can be found in the version index.

Quick Start

$header = new Smtpapi\Header();
print $header->jsonString();



If you are intersted in the future direction of this project, please take a look at our milestones. We would love to hear your feedback.

How to Contribute

We encourage contribution to our projects, please see our CONTRIBUTING guide for details.

Quick links:


smtpapi-php is guided and supported by the SendGrid Developer Experience Team.

smtpapi-php is maintained and funded by SendGrid, Inc. The names and logos for smtpapi-php are trademarks of SendGrid, Inc.

SendGrid Logo