Php form submits to different urls depending on what checkbox is selected

Hi,
I have searched everywhere and tried a few things with no luck.
I have a php form part of wordpress. I have the form submitting to wordpress and another user management system.

I want 3 checkboxes and depending which is checked, on submit the form data will go to a separate url.

I have this so far

<?php if ($_POST["checkbox"] == "Banking")
{
onsubmit="multiSubmit(this, 'url1');"
}
if ($_POST["checkbox"] == "Insurance")
{
onsubmit="multiSubmit(this, 'url2');"
} 
if ($_POST["checkbox"] == "Securities")
{
onsubmit="multiSubmit(this, 'url3');"
} 
?>

If i didn’t do the multiSubmit, the form would only go to wordpress. Right now with that code, I get an error. Any suggestions on why or better solution to how to do this?

Thanks