How to Disable plugin updates in wordpress

<?php remove_action( 'load-update-core.php', 'wp_update_plugins' ); add_filter( 'pre_site_transient_update_plugins', create_function( '$a', "return null;" ) ); ?>

Instructions:

This snippet simply prevents WordPress from checking if there’s any updates for your plugins.

This could be useful if you’re creating a website for a client, and don’t want them to update their plugins incase you have changed the code in it, or if you’re worried that the update will break the site.