What is the best visa option for a 9-month stay in Thailand while traveling with family?

Go Thailand 60 days, then Vietnam 1 to 3 months, then back Thailand, then Cambodia then back Thailand

There’s no problem flying in and out as many times as you want on 30 day exemption I just finished my 8th time in 8 weeks flew out this morning and got back 8pm tonight.

Vietnam and Cambodia are easy with hardly any restrictions or regulations at all. You can do a 90 day e-file multi entry to Vietnam just got mine for me and my family. I lived off and on in Cambodia since 2013 you can just get a visa on arrival go for the “ordinary visa” cost $35 I think and go to a Cambodian travel agency if you want a 3 month 6 month 1 year and up no problem I’m on my 9th 1 year visa that’s why I’m not sure of 30 day vis cost.

We’re on a 2 year walkabout ourselves before taking everyone to USA and the mundane life there 🤣

A multiple entry visa is a good way to get nearly 9 months of stay in Thailand. But it’s expensive. 5x the cost of a single entry visa and may not be necessary depending on your travel plans.

A single entry visa will give you 60 days and extendable for a further 30. If you plan to travel around SE Asia it may be cheaper to get that one, extend and then travel. Return on a free visa exempt entry and extend that. You can do that twice via a land border in a calendar year but technically no limit via air - until the immigration officer says you’re not allowed to anymore.

Yes the multiple entry tourist visa should work for you. Here is how this visa works:

The visa will be issued to you after approval and will be valid for 6 months from the day it's approved.

Every single time you enter Thailand during this 6 months, you will receive a tourist stamp giving you permission to stay in Thailand for 60 days. Each entry you can also apply for a 30 day extension.

So you are free to travel around SE Asia during the 6 months of your visa and each time you enter Thailand you'll get a fresh 60 day permission.

Just before your visa expires, the date written on the visa issued by the embassy, you would want to leave Thailand and re-enter. This will give you a final 60 days, and with this entry stamp you will definitely apply for a 30 day extension, giving you a final 90 days at the end of your 6 months. That is about 9 months which is what you are looking for.

Note that during this final 90 days you should either not leave Thailand since you no longer have a visa to return with, or you will want to apply and pay for a re-entry permit before you leave, that way you can re-enter on the final stamp you have.