Handy tips for filling out Westpac new account online. If you continue to browse and use this website you are agreeing to comply with and be bound by the following terms and conditions of use, which together with our privacy policy govern PNG Business Directorys relationship with you in relation to this website. Calculator. If the sending bank requires 11 characters, use WPACAU2SXXX Please also ensure the payer has your full 12-digit account number.