How can I open a bank account in Bangkok without a permanent address for my Non-O visa?

You should be fine, prepare a wise account in advance unless your bank does not charge fees or cheat you on exhange rates.

If all goes well you can transfer the 400k within 48h technically so your are not that short on time. Thai bank can be opened within the day, a bank or wise transfer can be 1 day.

Many will open if you buy a year insurance policy and a decent deposit

You are going about it the correct way. Get your non immigrant O in your home country. You can apply for your one year extension up to your final day of your 90 day stamp but obviously this is not advisable.

The problem with trying to open a bank account in Bangkok is that Bangkok immigration won't issue a certificate of residence until you have first done a 90 day report.

The process may be easier in your intended home base in Issan. Most immigration offices will issue a certificate of residence as long as you have registered your address by completing a TM30.

Armed with a certificate of residence, your passport with a Non Immigrant O visa and another form of ID (maybe a driving licence from your home country) you WILL be able to open a bank account. In my experience Bangkok Bank is the best account to deal with immigration issues and has the best English speaking staff.

If you run out of time opening the bank account and transfering the 400k you have the option as a married man to apply for a 60 day visit spouse extension.

Well, if you are going to stay permanrly in Thailand, why worry about 14 days?

I opened an account at Bangkok Bank by showing a hotel booking of one month and my non-O visa. It took me 2 days and numerous visits to do it. If I did it again, knowing what I know now, I'd use an agent to open the account.

Take your wife with you to the bank, makes it easier for you to open an account, best wishes 🤠

Are you already married to each other?

Hey i have 90 days tourist visa. From Canada so border run drive across Malaysia then return get 30 days?

I'll tell u how I did it, I did the 1 year extension just 2 weeks ago in Phuket. I did enter on a 60 days tourist visa. After that I did apply for a Non-o based on marriage. To get it you need some docs, you need a bank acc but you don't need any money. At least in Phuket. You need to have at least 3 full weeks left on your current visa/extension. Next, you have to transfer money to the bank acc, 400k+ thb, not important how you transfer them. They need to be in you acc 2 months before you apply for the extension. I did get the non o on 2.11.2023 and it was until 30.01.2024; So basically you have plenty of time to transfer the money and still have some days left before you apply for the extension. I did apply on 15.01.2024 and did get a consideration stamp until 12.02.2024. On 12.02.2024 I did just bring my passport and did get the 1 year extension until 30.01.2025. Only thing that you have to keep in mind is that they use to return you at least once to fix something on your docs, seems to be like a practice. So better plan 2 days for applying. And first go to the exact office where you gonna apply and ask about the docs, as it seems that not all of them follow the exact same procedure... At the end if you married, and bring the docs you get your visa, but keep in mind it did cost me ~5 days total.

You will really struggle to open a bank account without the correct visas nowadays, they have cracked down recently. You could use an agent to get one, it's not something I would do personally, but many people do.

The extension can be applied for on the last day of your visa entry stamp. The 15 day thing is if you're converting from a tourist entry to a non-O visa.