I have been studying in Thailand for 2 years and my student visa will expire on 20 april. In the same day I will recieve documents to apply for student visa again. Do I need to do visa run to get 30 day permit before apply for student visa ?

What do you have now? Do you have a valid non-ed visa or an extension of stay you applied for based upon attending a school at immigration?

If you are attending a formal school such as a university you should be able to apply for another extension at immigration.

I do have non-ed visa that will expire 20th april. I wonder if I can apply for extansion in the same day ?

normally they are asking atleast 21 days on your recent visa but I will be able to apply for it in the same day of expire..

7 minutes ago, b0n3meal said:

I do have non-ed visa that will expire 20th april. I wonder if I can apply for extansion in the same day ?

Yes

But I think it is your permit to stay that is ending not your visa that is expiring.

4 minutes ago, b0n3meal said:

normally they are asking atleast 21 days on your recent visa but I will be able to apply for it in the same day of expire..

The 21 days (15 days at most offices) is only to do a change of visa status to get a non immigrant visa entry not an extension application.

Oh you're right sir it is permit to stay. Thank you very much for help. Is there any forum topic about extansion of stay and which documents I need ?

42 minutes ago, b0n3meal said:

Oh you're right sir it is permit to stay. Thank you very much for help. Is there any forum topic about extansion of stay and which documents I need ?

Your school has to supply the supporting documents for the extension application. What is needed depends upon the type of school your are attending.