Assume that you have a valid VISA/Visa extension and you are forced to go back to your home country for a surgery.
You surgery, or the revalidation period, takes longer as the date of your next VISA extension.
Can you ask for a visa extension in your country or by post in this case (Medical urgency)?

No, no can do.

 

You can't apply for an extension if you are not in-country. At some point in the process you will have to present yourself at the immigration office

Plus the new stamp has to be put in the passport.

 

Unless there is some 'one-off, special consideration understanding', it's not possible.

 

If your permission to stay expires while you're out of country, it's not possible to extend it. You'll need to start over fresh. 

Maybe you could send passport to an agent . And get them to do it all.  On line 

4 minutes ago, yeahbutif said:

Maybe you could send passport to an agent . And get them to do it all.  On line 

Not possible. 

3 hours ago, DrJack54 said:

Not possible. 

I Heard of people get a visa extension without going to immigration.and no money in bank.. so why not.

32 minutes ago, yeahbutif said:

I Heard of people get a visa extension without going to immigration.and no money in bank.. so why not.

If he's abroad he'd have an exit stamp in his passport. Makes it kind of clear that no extension could be given I'd say.

Can only be extended in Thailand'.

Confucious say, Come back visa exempt.

1 hour ago, yeahbutif said:

I Heard of people get a visa extension without going to immigration.and no money in bank.. so why not.

Because he has an exit stamp in his passport and then it would be blatantly clear that the visa was given against the rules.

Would a trip to a Thai embassy work?

44 minutes ago, Krabi King said:

If he's abroad he'd have an exit stamp in his passport. Makes it kind of clear that no extension could be given I'd say.

I would also have a valid "Reentry" stamp in my passport and the Reentry stamp remains valable until entering Thailand.

6 minutes ago, FreddieMercury said:

Would a trip to a Thai embassy work?

No

Extentions are only issued by immigration. A embassy only issues visas.

1 minute ago, Confuscious said:

I would also have a valid "Reentry" stamp in my passport and the Reentry stamp remains valable until entering Thailand.

It also has expiration date on it.

33 minutes ago, FritsSikkink said:

Because he has an exit stamp in his passport and then it would be blatantly clear that the visa was given against the rules.

For all immigration officers to see that is.

1 hour ago, yeahbutif said:

I Heard of people get a visa extension without going to immigration.and no money in bank.. so why not.

Clearly you have no idea of how visas and stamps etc work.

As already mentioned by others.

Nothing an agent can do for the OP. 

On 2/20/2023 at 5:31 PM, Confuscious said:

I would also have a valid "Reentry" stamp in my passport and the Reentry stamp remains valable until entering Thailand.

The re-entry permit would expire on the same date as the visa/visa extension expires. 

On 2/20/2023 at 10:17 AM, Confuscious said:

Can you ask for a visa extension in your country or by post in this case (Medical urgency)?

The only thing you can ask for in your home country is a fresh real genuine McCoy non-immigrant visa (as opposed to one masquerading as an extension of stay) from the local Thai embassy!