What documents are needed for a Thai marriage visa extension and when should I apply?

To extend your one-year Thai marriage visa, you will need to gather the same documents as in previous applications, and it's best to visit your local immigration office in Khon Kaen for a definitive list. Generally, you can apply for your extension at least 30 days before your current visa expires, but you can also wait until the last day if necessary. Having sufficient funds in your bank account simplifies the process. It's encouraged to apply early to resolve any potential issues.