PHPMailer: Sending Mail Using Gmail SMTP

4 Sep

In today’s digital age, email communication is crucial for both personal and business purposes. One reliable way to send emails programmatically is by using PHPMailer with Gmail’s SMTP server. This guide will walk you through the steps to set up and use PHPMailer with a Gmail account, ensuring secure and efficient email delivery.


Before you start, make sure you have the following:

  • A Gmail account: Ensure that you have a Gmail account to use for sending emails.
  • PHPMailer library: Download and include the PHPMailer library in your project.
  • App Password: Generate an app password from your Gmail account to use for SMTP authentication.

Setting Up Your Gmail Account

To use your Gmail account with PHPMailer, you need to enable two-step verification and create an app password. Follow these steps:

Enable Two-Step Verification:

  • Go to your Google Account settings.
  • Under the “Security” section, find and enable two-step verification.

Generate an App Password:

  • After enabling two-step verification, go back to the “Security” section.
  • Find the “App passwords” section and generate a new app password. This password will be used for SMTP authentication instead of your regular Gmail password.

Installing PHPMailer

Download the PHPMailer library from the PHPMailer GitHub repository and include it in your project. You can also install it using Composer with the following command:

composer require phpmailer/phpmailer

Configuring PHPMailer with Gmail SMTP

Below is an example script showing how to configure and send an email using PHPMailer with Gmail’s SMTP server:

use PHPMailer\PHPMailer\PHPMailer;
use PHPMailer\PHPMailer\Exception;

require 'vendor/autoload.php';

$smtp_host = '';
$smtp_port = 587;
$smtp_username = '';
$smtp_password = 'your-app-password'; // App password generated from Gmail
$stmp_secure = 'tls';

$from_email = '';
$from_name = 'Your Name';
$subject = 'Test Email';
$message = '<p>This is a test email sent using PHPMailer and Gmail SMTP server.</p>';

$mail = new PHPMailer;
$mail->SMTPDebug = 0;
$mail->isSMTP(); // Set mailer to use SMTP
$mail->Host = $smtp_host; // Specify main and backup SMTP servers
$mail->Port = $smtp_port; // TCP port to connect to
$mail->SMTPAuth = true; // Enable SMTP authentication
$mail->Username = $smtp_username; // SMTP username
$mail->Password = $smtp_password; // SMTP password
$mail->SMTPSecure = $stmp_secure; // Enable TLS encryption, `ssl` also accepted

$mail->setFrom($from_email, $from_name);
$mail->addAddress('', 'John Doe'); // Add a recipient
$mail->addCC('', 'Steven Doe'); // Add CC recipient

$mail->isHTML(true); // Set email format to HTML
$mail->Subject = $subject;
$mail->Body = $message;
$mail->AltBody = strip_tags($message); // Plain text body for non-HTML email clients

if(!$mail->send()) {
    echo 'Message could not be sent.';
    echo 'Mailer Error: ' . $mail->ErrorInfo;
} else {
    echo 'Message has been sent';

Explanation of the Code

PHPMailer Setup:

  • Import the PHPMailer classes using use PHPMailer\PHPMailer\PHPMailer; and use PHPMailer\PHPMailer\Exception;.
  • Include the Composer autoloader if you installed PHPMailer using Composer.

SMTP Configuration:

  • Define the SMTP server settings including host, port, username, password, and security protocol (TLS).

Email Composition:

  • Set the sender’s email address and name using setFrom().
  • Add recipients using addAddress() and addCC() for CC recipients.
  • Set the email format to HTML with isHTML(true) and define the subject and body of the email.

Sending the Email:

  • Use the send() method to send the email.
  • Check if the email was sent successfully and handle errors if any.


If you encounter issues, here are some common problems and solutions:

  • SMTP Connection Failure: Ensure that you have the correct SMTP host, port, and security settings.
  • Authentication Errors: Double-check the app password and ensure it is correctly copied from your Gmail account settings.
  • Firewall/Antivirus Interference: Sometimes, firewall or antivirus software may block SMTP connections. Make sure to configure them to allow outgoing SMTP connections.


Using PHPMailer with Gmail SMTP is a reliable and secure method to send emails from your web application. By following the steps outlined in this guide, you can set up and configure PHPMailer to work with your Gmail account, enabling you to send emails effortlessly.

For more detailed documentation and advanced configurations, refer to the PHPMailer official documentation.