Do I really need 500,000 THB in the bank for the DTV, and for how long?

The number itself is not negotiable. How you show it is where applications succeed or fail.

What the requirement is

Financial evidence of at least 500,000 THB, which the Royal Thai Embassy in London converts to 12,000 GBP. The money stays yours, in your own account, in your own country. Nothing is transferred to Thailand and nothing is frozen. Currency Check gives you today's figure in your own currency.

How long it has to sit there

The period depends on the post. ThaiLawOnline, comparing missions, reports that Washington asks for three months of statements each ending at no less than 500,000 THB, while the London page states the amount without a statement period. Thai Visa Services describes three months as the standard officers look for, and says they check that the balance was held throughout, not only on the last day.

The same source puts fund parking, a sudden deposit within the 90 days before you apply, at the top of its list of refusal reasons. If a friend is lending you the money for a fortnight, expect the application to fail, and the 10,000 THB fee is not refunded on rejection.

How to plan the timing

1. Work backwards from your travel date: three months of statements, plus five to fifteen business days of processing, plus the time your police certificate takes.
2. Move the money in early, then leave it alone. Regular income on top of it helps rather than hurts.
3. Download official PDF statements showing your name and account number on every page.

Which accounts count

Thai Visa Services says a personal savings or current account in your own name is what posts expect, that joint accounts are accepted by some missions and refused by others, and that investment, brokerage, crypto and fund balances are not accepted as the main proof. We found no official text that settles joint or business accounts, so ask the post you will apply to before you move anything. The complete DTV guide has the full document list.