Include PHP File in WordPress

Last Updated: November 16, 2025

Written By: Nasrumminallah Zeeshan, WordPress Technical Writer, WP Tech Support

If you want to include a PHP file in WordPress, you have come to the right place.

Including a PHP script in WordPress may result in security issues. For example – if you include one That allows users to execute PHP codes, your site is at risk.

This resource will cover how to include a PHP file in WordPress. How you include PHP files in WordPress can affect a WordPress website, such as using manual routines to include WordPress files, changing core files, or using WordPress plugins.

Let’s proceed to describe the matter in more detail.

Personal Opinion

At WP Tech Support, we often receive requests from clients, asking for help regarding file management in WordPress.

Here is what we’ve found so far.

What is PHP?

PHP is a scripting language for web development and dynamic applications. If you want to create a dynamic application that runs on the Internet, PHP helps you perform scripting on a web server, such as Apache.

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In this case, scripting means compiling and running PHP scripts on the Web. The applications programmed using PHP are called PHP scripts, programs, or web applications in general.

PHP is required to create custom web applications and run PHP scripts on a web server, such as an Apache web server.

Introduction to PHP Files

Note: PHP files are regular files that support and can run PHP-based files on server ends. The server should have PHP installed if a web application is built in PHP.

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PHP files perform specific tasks on a WordPress website. In this case, the WordPress infrastructure is developed in PHP and supports PHP applications without supporting dependencies.

As described above – PHP is a scripting language that helps admins create dynamic applications and specific functions; you can develop WordPress themes, plugins, or custom applications in WordPress using PHP programming.

PHP Files and WordPress

Using PHP programs in WordPress is called creating custom scripts to extend WordPress functionality. If you know how to build PHP scripts, you can use WordPress for custom applications, purposes, or scripts.

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In this case – once you have created a custom program using PHP, you must upload the script to WordPress and make it applicable to WordPress. Uploading files to WordPress root may require FTP or the web version of cPanel File Manager, where you can upload/download files.

We can now address the subject matter – how to include and make a custom PHP script usable in WordPress. However, including PHP files in WordPress has the following aspects: not just uploading PHP files to WordPress root.

• Running a new PHP script on a WordPress website
• Uploading PHP files to custom WordPress sites
• Running test PHP files for A/B testing purposes
• Using a staging website for testing, editing, and managing PHP scripts

Note: In the scenarios above, you can use WordPress to respond to new PHP files.

Include PHP File in WordPress

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Let’s include a PHP file or script in a WordPress website. You may need to use a WordPress FTP account, an FTP client like File Zilla, or access to cPanel File Manager.

Please note that adding PHP files to WordPress may have different intentions. Here, we aim to address common scenarios. Keep the same if you need to learn how to proceed. Also, ensure you’ve taken WordPress backups before making any changes.

One way to include a PHP file in WordPress is to use the include function. It is applicable if you’re using custom PHP scripts. The include function is a PHP programming aspect of including files in WordPress. The function helps users programmatically include a file in coding, allowing web applications to use and process the included file(s). You will only undergo such maneuvers if you know the PHP language.

For example, you can use the include function if your PHP script works under the WordPress root directory. However, the custom script you use for the “include function” may not work if placed outside the WordPress root folder.

In this case, you must upload the PHP script to the directory where you would like to keep the calling PHP file. As discussed above, use the FTP client (File Zilla) or cPanel web version interface to upload files to the WordPress root directory.

In this case, once uploaded – use the include function described in the following line.

Include(‘path/to/folder/custom-script.php’);

In addition to the above code, you can use another syntax, get_template_part().

Note: Please only proceed with programming codes if you can create and set up PHP scripts or snippets.

However, if you want to run your scripts using the WordPress database, you must use WordPress’ recommended and supported functions and hooks for custom PHP scripts.

Let’s describe another method to include a PHP file in WordPress.

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If you need to be more technical and want to add new PHP files to WordPress, you can follow the following routine.

It is better to install and use a WordPress plugin for this purpose. Once you have installed a WordPress plugin, you can include or insert a PHP file in WordPress.

For example, Code Snippets is a plugin that helps users add and run PHP scripts or HTML code snippets on WordPress pages and posts.

In such scenarios – you can skip editing the WordPress theme’s Functions.PHP file using the WordPress editor.

If you need to be more technical, the Code Snippets plugin helps skip complex algorithms when inserting PHP.

By using a WordPress plugin, beginners can use PHP scripts using a graphical user interface, where adding, editing, and managing custom PHP scripts becomes an enjoyable routine for WordPress beginners.

In simple words, such plugins help users run PHP scripts in WordPress – without learning how to add code snippets to a Theme’s Functions.PHP file.

Note: If you want to alter code snippets in a WordPress Header and Footer, you can also use specific plugins. The WordPress official Plugins Directory quickly provides suitable candidates for this purpose.

Professional Tips

• Depending on the requirements, you should learn how to add PHP scripts to WordPress. Regular users don’t need to add PHP files to WordPress, but developers need such routines for performance, functionality, or development purposes. In this case, even if you’re using a plugin to include PHP files in WordPress, don’t proceed or make changes if you don’t know how the PHP language works. The result is severe consequences as the process may need WordPress developer skills.
• To include a PHP file in WordPress, specify the absolute or relative file paths in WordPress scripts. Research various URL structures online for more information.
• Adding PHP scripts for simple routines, such as tracking code snippets, is simple; WordPress plugins can help. However, running PHP scripts in WordPress is different and may require programming skills. Including a PHP file for tracking purposes involves uploading a file to the WordPress root directory. You can achieve this with everyday routines, such as using an FTP client to upload files to WordPress.
• Depending on a Theme’s functionality, adding PHP scripts or code snippets can break a WordPress Parent Theme, Plugin, or website. In this case, you need to follow code standards. It is better to follow a Theme’s official resource or tutorials to include PHP files in WordPress or the theme folder on a child theme.
• Sometimes, you can extend WordPress functionality without adding a PHP file to the WordPress root directory. In this case, tweaking the cPanel directory’s content can help you get things done. For example – changing the HT-Access file’s content without changing or adding PHP scripts can help you configure WordPress areas, such as Redirects in WordPress.
• If you need to change PHP scripts due to a WordPress plugin, it is better if you have taken your site’s backup. In general, you should always back up your site’s content before making changes in WordPress – such as adding custom PHP code files in WordPress.

Over to You

When it comes to including a PHP file in WordPress, don’t consider things as a regular user of WordPress. The subject matter has a different approach and requires technical expertise.

Instead, consider the developer’s aspect of including a PHP file in WordPress.

As described above – including PHP files in WordPress refers to calling new PHP scripts from programming scripts in WordPress, not uploading PHP scripts to the WordPress root directory.

However, once you have uploaded a PHP file or added a PHP code snippet to WordPress, you should be able to call the particular script from anywhere in WordPress, which will help you run, edit, and execute PHP programs in WordPress.

If you lack technical expertise while editing PHP files in WordPress, let us know your thoughts so we can help you with WordPress infrastructure—including WordPress maintenance, performance improvement, and security updates regarding PHP infrastructure.

About the Author: Nasrumminallah Zeeshan

Nasrumminallah Zeeshan is a WordPress Specialist and Lead Writer at WP Tech Support. He brings seven years of deep expertise in managing and securing high-volume WordPress installations, with a core focus on database optimization and maintaining the stability of the WordPress core. His mission is to simplify complicated WordPress trends and products, helping readers and customers understand and implement best practices through practical, easy-to-digest educational content.

Connect with Nasrumminallah Zeeshan on LinkedIn.