Can I renew my NON OA retirement visa while in the USA or should I apply for a new one?

This is not a visa but an entrance stamp. As you left Thailand already, it is not valid anymore. On your visa is the last day that you can enter Thailand. If that has already passed you need to apply for a new visa

Michael Ganzermiller.

Since your current O-A Visa that you have is still good until sometime in Jan 2021.

If you could get into Thailand 45 days or more before it Expires - then you could go to Thai Immigration and apply for a one year Extension of Stay. You technically need proof of 800,000 Baht in a Thai Bank two months prior to applying... But considering Covid Lockdown problems they might be forgiving of the two months Seasoning. You would have to have the Health Insurance and the Specific Covid-19 Insurance. Both a bit expensive. Plus 10 to 14 days in a quarantine hotel (expensive)

Another way to do it... But probably better to wait until Feb / Mar - get a new O-A - with luck some of the barriers may be lessened

Did you get a re-entry permit before you left Thailand?

If U got the is in your country then it is multiple entry and if in the first year if U go back to Thailand now it will be stamped for another year as I have done this

To get an O-A Visa - a person has to apply in the Home Country at a Thai Consulate / Embassy

In the first year of the O-A Visa - the Visa is Multi-Entry with unlimited exits and entries back into Thailand. No reentry stamps are needed. If you really have an O-A Visa and are in the first year

One of these mate cost just over a 1000 baht in the air port.

You need a re-entry permit or a valid visa. That stamp is worthless

Get a new one in America - much simpler

You can only get a one year extension within Thailand. If you are outside Thailand when it expires, you will have to apply for a new OA Visa.

You can enter on that visa until 11 Jan 21 then it expires.

You’d have to apply for a new visa.