What is the S21 form?
This is basically a 100 points ID check form you would normally need to do if you open a bank account or apply for a credit/debit card in Australia. You simply need to identify your self in front of a referee (like a Justice of Peace or other), who confirms that he or she viewed your ID. This is a standard requirement for financial transactions in Australia and you should do it as soon as possible if you are planning to deposit more then $1000 onto your card.