This is the Australian partner migration process. There are different categories which Australian Sponsors can apply for their girlfriends, partners and spouses from Thailand. The type of visa shall vary depending on the intention of your visa application. Note that if you are married to a Thai national then a marriage registration certificate would be needed. Speak to a Thailand lawyer for more information.
Australian Partner Migration
One of the most common is an Australian Fiancée visa called the Prospective Marriage (temporary) – Subclass 300 visa. This type of visa is solely for those who are planning to get married in Australia. And it 
is important that the applicant provide a proof that he or she is single or divorced to apply for this type of visa. The fiancée visa for has a validity of 9 months, upon arrival in Australia. During this time, marriage shall take place. By then, the process for a Subclass 100 be submitted once married in Australia to enable the applicant to stay permanently in Australia.
If you have lived together in Thailand with your partner, then you might also want to contemplate for partner visa application. This would be applicable for those in relationship, in a commitment, in a partnership or for unmarried couples.
And last option is to apply for your spouse to join you permanently in Australia. This is under a Spouse visa application and is only applicable if you are married to a Thai national. Also take note that if you are going or have any dependent children from previous relationships which you have planned to be included on your visa applications, then you must check on legalities as there maybe some limitations on them in entering Australia
There can be problems or delays that may occur in relation to inappropriate forms, incomplete details and requirements submitted. So, it is best to speak with an attorney about all these as such processes would require a specific documentations and should be submitted correctly. Always take proper guidance when dealing with Australian migration.
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