rewrite then redirecting to same page with .htaccess

Question

Default URL: domain.com/contact.php

Rewrite URL to: domain.com/contactus

Then when I have to enter the default URL to: domain.com/contact.php it should redirect (open) to domain.com/contactus

I have tried

RewriteRule ^contactus$ contact.php [L]
RewriteRule contact.php contactus [NC,R=301,L]

Answer 1

You need one redirect rule to force new URI in browsers and one rewrite to forward new URI to php file:

RewriteEngine On

# redirect rule
RewriteCond %{THE_REQUEST} \s/contact\.php[?\s] [NC]
RewriteRule ^ /contactus? [L,R=301] 

# rewrite rule
RewriteRule ^contactus/?$ contact.php [L,NC]

? in target URI will remove existing query string.