What is the financial requirement for sponsoring a spouse and two children with a DTV in Thailand?

It's somewhat depends on the age of the children, young kids under 10 most likely can use the main DTV applicant funds of 500k. You have to show financial stability and Independence.

First you apply for yourself, after getting approved the other 3 apply separately as dependents. You are sponsoring them, so you will need 2 million, 500k for each

It is embassy-dependent. Just looked up the information for the Thai embassy in Argentina and it says 500k per person.

I submitted the same bank account information for my wife and 4 children and it was accepted without issue.

It’s arbitrary. Depends entirely on the consulate and their house rules and who is looking at your application. Some say when you sponsor someone you need to reprove your own financial standing in addition to the person you are sponsoring. But if you dig through this group you’ll see that it’s nebulous and there are consulates that implement things differently. A lot of it depends on the information you offer up in your application, the consulate you are applying at, etc. There are agents who also do an overkill approach with paperwork cause they would rather waste your time and have you over prepare a bunch of papers cause they don’t want to have to refund you if you’re denied, so they have you exhaust every scenario upfront. So depending on where they apply, expect to sponsor someone starting at 500,000 baht but be prepared if they ask for more proof.

Officially the requirement is 500,000 for each applicant, but most embassy only enforce this for adults, so normally 1,000,000 for you and your wife should be OK.

I did my two kids under me and they just asked for financial proof of 500,000THB in my name, so you should be fine

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