Sorry I'm sure that this must have been covered loads of times, but can't find answer. If you have a muli non imm o, stamped for 90 days, can this be extended by immigration without exiting the kingdom.

Check the '400,000 deposited' topic a little further below. This has good info on how to dispense with any 'Category O' visa runs post 90 days.

Sorry I'm sure that this must have been covered loads of times, but can't find answer. If you have a muli non imm o, stamped for 90 days, can this be extended by immigration without exiting the kingdom.

Are you of retirement age or married to a Thai or have a Thai child ?

DPP

I am over 50: no Thai child (to the best of my knowledge)

Not averse to non imm O "A". Am currently living in Chonburi. Can I do this in Pattaya?

It is an O visa( O-A is obtained from abroad ), and you can extend it for a year each year at Pattaya Immigration. You must have a bank account in Thailand with 800,000 baht in the account. Once the account is set up, you need a very current letter ( within 7 days of applying ) from the bank. Take the letter to Immigration, along with your passbook,and you should be fine. If you plan to travel out of the Kingdom, get a re-entry permit from Immigration as well. If you reenter Thailand without that permit, you will invalidate your extended visa. After 3 consecutive years you are eligible to apply for residency.