I dropped an email to Bangkok Bank and they replied promptly.
It seems to obtain online statements via the app, you need to Register in advance.
I post below their reply, for anyone interested in this info.
I am not sure what this means - Please be advised that international transfers in the statement will display only the transaction code and transaction name.
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Thank you for contacting Bangkok Bank
In the event that you would like to obtain your Bangkok Bank account statement, please be informed that you can request a bank account statement through the channels listed below:
Via Mobile Banking. If you have already registered, you can request an account statement by selecting 'More Services' menu on the home page. Then, select “Request account statement”. This function will provide your transaction history for up to 12 months and send the statement to your email registered with Mobile Banking within one hour with no fee. Please note the following:
The statement history you receive will be updated as of yesterday.
For requests submitted before 09:00, the statement history will be updated as of 2 days ago.
Via Bualuang iBanking. If you have already registered, you can view your savings account activity dating back to 6 months by clicking on your account number on the 'My Accounts' page. Then, select the period time on 'Transaction Date Range'. You can also download or printout by clicking on the menu on the top of the account activity page.
At Bangkok Bank branch. Please ensure to bring along your valid passport and account passbook as the required documents. Kindly note that a fee is applicable for the request of a savings account statement. The details are as follows:
100 THB for requesting a Savings Account Statement dating back no more than 6 months
200 THB for requesting a Savings Account Statement dating back over 6 months to 2 years.
500 THB for requesting a Savings Account Statement over 2 years.
Statements dating back no more than 6 months can be received instantly. However, for statements dating back more than 6 months, you may choose from one of the following methods to receive your statement:
Through a branch - it will take 2-5 working days for the bank to process
Through email in PDF format - for requests made before 4:00 p.m., you will get the statement on the next day at 02.00 p.m.
Please be advised that international transfers in the statement will display only the transaction code and transaction name.
Should you require any further assistance, please let us know. You can also contact our phone banking center at 1333 (for domestic) or (66)26455555 (for overseas) during all hours to acquire more information.
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