// POSTCODES - will work for every UK postcode including the very strange GIRO Bank one.
$pattern = '/(^gir\s0aa$)|(^[a-pr-uwyz]((\d{1,2})|([a-hk-y]\d{1,2})|(\d[a-hjks-uw])|([a-hk-y]\d[abehmnprv-y]))\s\d[abd-hjlnp-uw-z]{2}$)/i';
if (!preg_match($pattern, $postcode)) {
    // Display Error
}


// Valids all uk numbers including +44's or anything like that
$telephone = str_replace(" ","",$telephone);
$telephone = str_replace("+","",$telephone);
$pattern = '/^01[1-9]{1}|02[03489]{1}|05[0-9]|07[056789]{1}|08[047]{1}|441[1-9]{1}|442[03489]{1}|445[0-9]|447[056789]{1}|448[047]{1}$/Ui';
if (!preg_match($pattern, $telephone)) {
    // Display Error
} else {
    if(substr($telephone, 0, 2) == "44") {
        $telephone = "0" . substr($telephone, 3, strlen($telephone));
    }
    if(strlen($telephone < 10)) {
        // Display Error
    }   
}