What paperwork is needed to extend from a 60-day tourist visa to a Non-O visa in Thailand?

Please NOT post requirements lists for a 1-year extension based on retirement or those from other provinces.

You cannot extend an entry stamp on a tourist visa or visa-exempt scheme for Non-immigrant based reason. You have to apply for a new in-country initial Non-O visa based on being over 50.

This is a new visa application, your 90 days would start on the day of visa issuance, usually after an under-review period of 21 days in CM. 90 days of a new permitted-to-stay stamp will not be added like a tourism extension.

In Chiang Mai, you need to have 21 days (actually 15 working days) remaining with your current stamp to be able to apply for an in-country visa.

This is a bit old general requirements list for an in-country Non-O retirement visa, not Chiang Mai specific. You better check with CM for their latest requirements list as they have their own list for sure.

/9.FOR-RETIREMENT-PURPOSES-50-YEARS-OLD-NON-O.pdf