When can I apply to extend my Retirement Non-O Visa before it expires in Thailand?

The earliest time to apply for extending your Retirement Non-O Visa is generally 30 days before the expiration date at most offices, meaning you can start applying after December 15, 2022. However, certain locations like Chiang Mai and Bangkok allow applications 45 days in advance, so you could apply as early as November 30, 2022. Locations such as Hua Hin also permit applications 45 days prior.