I will be moving back to Thailand in September from the US. My wife is Thai, so I intend to get a Non-Immigrant Visa (O). It looks like I can apply for the visa via thaievisa.go.th I have no experience using that service/website.

 

My question is this: When should I apply for the visa? Is it effective immediately upon issuance or upon entry? I don’t want to apply too soon and cut myself short a couple months, assuming it becomes effective immediately (may not be the case?). If I apply soon, is it possible for the visa to not be valid until September? I need to utilize the full year of the visa, so I don’t want to cut myself short by getting the visa too early.

 

Any advice would be appreciated.

A single entry non immigrant O visa is valid for use for 90 days from date issued and provides a 90 day stay on entry.  There is no one year stay unless you extend inside Thailand using TM7 application and meet financial requirements and such.  There is a multi entry type O visa that is valid for use from date of issue for one year and provides unlimited number of up to 90 day stays during visa validity.  Perhaps that is what you mean?

 

It appears if multi entry visa is the option you do not want to obtain too early.

OP, you have clear answer above.

 

So are you applying for ME Non O 

That is a visa valid for 12 months and yes you do not want to apply for that too early. 

 

A single entry Non O is valid for 90 days from the date it is issued. A multiple entry Non O is valid for one year from the date it is issued. When you enter Thailand with either a single or multiple entry visa, you are given an initial 90-day permission to stay. If your plan is to live in Thailand with little or no international travel, get a single entry Non O visa, and apply for one-year extensions of your permission to stay at the local immigration office. If you plan to travel in and out of Thailand on a regular basis, get a multiple entry Non O visa fairly close to the date of your journey in September, and plan on leaving Thailand at least every 90 days (can be 150 days with an easy to acquire 60-day extension).

Don't know where you are located but I recently did a 1 year non imm O using the Thai Embassy in London. Applied early hours of 9th June, visa fee deducted 9th June and visa approved on 15th June. Think it mentioned 15 days if all goes well on the website. 

This is helpful. Thank you all for the responses.

I don't believe I'll be going in and out of the county much, so it sounds like my best option is the single entry non immigrant O visa and plan to get a one-year extension while inside Thailand.