The classic email sending library for PHP

Simple, modern & fast web-based email client

Cypht: Lightweight Open Source webmail aggregator [PHP, JS]. Supports IMAP/SMTP, JMAP and EWS (Exchange Web Services)

Buggregator is a lightweight, standalone server that offers a range of debugging features for PHP applications.

A PHP library for performing email addresses validation via SMTP

Library to send e-mails over different transports and protocols (like SMTP and IMAP) using immutable messages and streams. Also includes SMTP server.

Configure Magento 2 to send email using Google App, Gmail, Amazon Simple Email Service (SES), Microsoft Office365 and many other SMTP (Simple Mail Transfer Protocol) servers

Magento 2 SMTP Extension helps the owner of store simply install SMTP (Simple Mail Transfer Protocol) server which transmits the messages into codes or numbers.

Aplus Framework Email Library

Buggregator local debug server for PHP projects as composer package

Eventum Issue Tracking System

🌟 FastSitePHP 🌟 A Modern Open Source Framework for building High Performance Websites and API’s with PHP

SMTP server (library) for receiving emails, written in pure PHP.

A lightweight PHP SMTP mail sender

Send Templated emails with WordPress

A fast, simple yet very efficient email queuing system for PHP/MySQL

Simple PHP SMTP Mail Send Script

Provides a clean and simple way to configure the WordPress-bundled PHPMailer library, allowing you to quickly get started sending mail through a local or cloud based service of your choice

Secure Bootstrap contact form with AJAX submission. It features both PHP and JavaScript input validations, SMTP mail sending, domain rejection for non-existent domains, and Google reCAPTCHA v3 integration. Best of all, it’s completely jQuery-free !

🌰️🐿️ SquirrelMail GitHub Repository (PHP 7-OK!)