What should I do if I don’t have a business registration while applying for a Thai visa as a freelancer?

Since you can provide the registration letter and your 350euro are gone, I'd try to write a cover letter (chatgpt is your good friend) stating that according to the law in your country you aren't supposed to have any but then you should be able to prove that money from your clients goes regularly into your bank account. I'd also send portfolios, example of your previous jobs, emails with your clients and whatever can support the fact you're a freelancer. Even that might not be enough but at least you tried

Since you are applying under the freelancer category—which is one of the most difficult categories to get approved—you should include strong supporting documents. Many applicants have previously submitted unverified or misleading documents, so Thai embassies now require third-party evidence that can be independently verified.

You may submit alternative supporting documents such as:

• Recent tax returns showing your income source

• Professional qualifications or certifications

• Your LinkedIn profile or personal website

• Any official contracts, client invoices, or recommendation letters

These documents will help convince the embassy that you are a legitimate freelancer with a stable and verifiable income.

Apply as soft power

Oh my god just change country to apply. In my home country of Singapore darn difficult (we don't have bilateral agreement of this arrangement yet 😕) I just head to another SEA country. Approved today.

I faced the similar same prob as a freelancer. I sent a letter to the Taipei embassy explaining the problem, they said apply with what you can, You could try similar, you can also upload business registration details of your client, which I did in the end.

In many countries, you need to register a business to legally work as a freelancer.