If you want to change your surname after the wedding you will need to apply for a registered copy of your marriage certificate with Births, Deaths and Marriages (BDM) in the state the marriage took place. (Please note that it is not a legal requirement that you change your name.)

The wedding certificate you are given on your wedding day will not meet the identity requirements of many government agencies (e.g. Transport Dept, Passport Office, Medicare, etc) and banks if you want to change your name.

Once you receive the registered certificate from BDM, you then take this with you to the relevant organisation and they will adjust their records to reflect your new surname accordingly. (Check to see what other forms of ID you will also need to take. For example, your Birth Certificate.) The certificate you receive from BDM will not have your married name on it, it will still have your maiden name; it is purely proof of marriage only.

You will find all the information (including costs) and application on their websites.

Qld BDM: www.justice.qld.gov.au/justice-services/births-deaths-and-marriages/marriages/marriage-certificate

NSW BDM: www.bdm.nsw.gov.au/marriages/marriages.html