If you live in the EU then you will be glad that prenuptial agreements are enforced in the EU. The Hague Convention covers the Matrimonial Property. If you are from Austria, Greece, and France or even from Spain, Luxemburg, Portugal, Switzerland or Sweden then the agreements should be of no surprise to you.
EU: Prenuptial Agreements
When you register your marriage in Thailand you will also need to register your prenuptial agreement at the same time. You cannot register the prenuptial after you have already registered the marriage. That would require an expensive application to court and the legal system in Thailand is very slow and costly. Plan early by contacting a lawyer in Bangkok or a lawyer in Phuket for advice and guidance and have your marriage registered with your marriage.
Should a divorce occur in a European country the courts will firstly look at a number of issues much like the UK. They will check if the agreement is against the moral values in Europe. They will also check to see if it is illegal or that there was duress and one of the parties had been forced to sign the agreement against their will. Lastly they will check to see if both parties understood the agreement when it was signed. The agreement has to be drafted in such a way that it complies with two countries laws.
Note that there may be a conflict of laws when comparing the EU with Thailand. As an example a deaf person cannot be a witness to a legal agreement or it will be called into question in terms of the Civil and Commercial Code which governs Thailand. European law however does not have a stipulation that a deaf person may not sign the agreement. Hence it is always best to seek advice from an expatriate law firm in Thailand where they understand both Thai law as well as EU laws and draft the agreement so that it fills the requirements of both Thailand and the European Union.
When drafting a legal agreement when it is between two parties from different cultures and countries you also have to ensure that your Thai wife understood the agreement. You would need to have proof that it was understood as most times during a divorce the agreement goes down the memory hole of marriage. Normally your Thai fiancée would be taken to a different law firm to explain to her what the agreement states and they will provide a letter to state that she understand the agreement in full. This letter would been used a proof if she later claims not to have understood.
If you are considering marriage in Thailand and filing a prenuptial agreement as the same time then speak to an attorney in Thailand such as GAM Legal Alliance in Bangkok for sage legal advice and assistance. You could lose all you have if things do go wrong.