Using 503 page when my site is in maintenance mode

This is my code for 503 page:

header.php

if(getOption('maintence_mode')==1)
{
header("location:503.php");
exit;
}

503.php

    
    
    
    Page Not Found 

    

    

    
    
    Site is currently in maintenance mode.
    
    

I want to know if my code is correct and how Google will handle SEO thing. I don't have much knowledge about this, so it would be very helpful if someone could validate this code.

It looks good to me, but I do have one thing to say.

If I want to access http://yourdomain.com/example/page, and get a 503 error, I want to be able to refresh the page in a little while, to see if the 503 error is lifted.

What you do is redirect the user to the 503 page, which means that the address I'll get now if I refresh is http://yourdomain.com/503.php, this is not optimal.

Instead of redirecting, include the 503 error page.

Also some other things:

• The error says 503, but your titles says "Page not Found"

• Code indentation is important. Don't neglect it!

• Never use an if block without curly brackets. Never.

StackExchange Code Review Q#60467, answer score: 38