What are the requirements for maintaining a retirement visa in Thailand regarding time spent in the country?

I suppose you not mean the retirement visa that give you 90 days, but the 1 year temporary extension (TM 7), yes then you are free to go in and out as much as you want within the validity of your extension, if you buy a reentry permit. I do it same way now and spend 6 months in Norway and 6 months in Thailand, easy.

Up to you. You are not obliged to spend your time in Thailand. But think of an extension with multi-entry when you might visit other countries during the lenght of your extension.

So why do you want a retirement visa if not retiring here

Just make sure you're back in time to renew your annual extension of stay, and get a reentry permit every time you leave.

What is a retirement visa?

*** The Non-Imm-O Retirement Visa is a 90 days single-entry visa, you will get stamped in for a 90-days stay permit.

This stay permit you extend for 12 months inside Thailand, by fulfilling the requirements, mainly the financial requirements.

The 1 year stay permit doesn't have a re-entry permit built in, so if you want to exit and re-enter Thailand during this one-year stay permit, you need to buy a multi re-entry permit for 3800 Baht to keep your stay permit alive.

With a multi re-entry permit you can come and leave as many times as you wish.

You need to be back in Thailand before your 1-year stay permit expires, because you must apply for a new 1-year extension of temporary stay permit, again, every year

Can you get a multi entry retirement visa

If you fulfill all requirements for your EoS (extension of stay 12 minths) each year, you need only to be in Thailand for the next EoS.

You need to buy before leaving Thailand each time a re-entry permit

As long as you pay for a re entry permit each time you go out no problem

I have nonO and I love that I have the flexibility to travel outside Thailand and have it as my base for insurance purposes etc.

After you get your first extension of stay, just make sure you are in Thailand for your next extension of stay permit. My province lets me do mine up to 45 days before expiry which gives nice flexibility.

Make sure you have reentry permit before leaving Thailand. When I do my extension of stay, I go ahead and get multiple reentry permit so I don’t have to think about it before trips.

Be sure to follow rules for bank amounts etc

What are you calling a retirement visa?

The Non-OA 12 month visa comes with re-entry built in for the 12 month period

The Non-O is a 90 day visa which you extend for 12 months inside Thailand, it doesn't have re-entry built in so you need a re-entry permit to keep your stamp alive

To get another extension inside Thailand you need to be back in good time before your stamp expires but otherwise you can come and go as you please

If you get the retirement visa you will have to be back to do the extension before it expires and you need to keep the funds at the required level

I don't know the answer and would like to hear what others say. However, if you would like to be on the SAFE side, I would suggest one of the DTV tracks. The RETIREMENT visa, DOES NOT ALLOW work or volunteering, and that can get boring after a while (as several retirees in Thailand have told me). Also, the DTV BUILDS IN MULTIPLE RE-ENTRY for up to 5 years at a time.

Look up "Destination Thailand Visa" online to learn more about the various options (there are SEVERAL DTV tracks available, each with slightly different requirements).

You will need a re entry permit but don’t get why you need the retirement visa now

Why go to all the trouble of getting a retirement visa if you just want to visit from time to time, your making no sense at all.