  # Change domain.com to be your primary main domain. http://domain-b.com/ RewriteCond %{HTTP_HOST} ^(www\.)?domain-b\.com$ [NC] # Change 'subfolder' to be the folder you want to redirect request to. RewriteCond %{REQUEST_URI} !^/domain-b/ [NC] # Change 'subfolder' to be the folder you want to use for your primary domain. RewriteRule ^(.*)$ /domain-b/$0 [L]