Can I apply for a visa extension in the UK before traveling to Phuket?

When going to Thailand for 31 - 60 ( 90 )days, the 60 days touristvisa is the best option.

It is cheaper than visaexcempt + 30 days extension.

No need of a onward ticket ( 90 days 1 onward ), if returnticket within 60 days.

It is easier to apply from the comfort of your home.

thaievisa.go.th

Not wasting holiday time to find, go to and waiting at a immigration office ( 90 you would need that ).

No need to leave Thailand in up to 90 days.

No question is stupid when it involves immigration in any part of the world.

You can't get an extension before leaving the UK, you can get a tourist visa which is good for 60 days. Much easier than having to extend a 30 day visa exempt entry at an immigration office inside Thailand

Avoid the long lines with an online appointment.

Arrive 30 days visa exempt and then extend another 30. Note, the 30 days are added to your stamp, there's no penalty in going early

Emily, do yourself a favour, get a 60 day visa whilst in the Uk, seriously it means you can get it sorted before you fly, that alone will reduce your stress levels, you can apply online (make sure you use the correct Thai Embassy website to avoid any scams) once it’s done, you are good to go just make sure, once you land and go through immigration, make sure they stamp you for 60 days and don’t inadvertently make a mistake and stamp for 30 days

Enjoy your visit

You can apply for a 60 day tourist visa from home.

I'd recommend you do that.

Or arrive exempt for 30 days and extend in country for 30 days at immigration.

Just apply for a 60-day tourist visa before you leave UK

It's much easier and cheaper to apply before you travel