Is it enough to copy frontpage and the pages that are stamped with visas etc.. Or does immigration want copies of the empty pages also? 

Some offices want every page of old pp.

Some just the Photo page last entry stamp any pages with visa stamp.

If currently on extensions then the visa (eg non O) that those extensions are from.

Obviously reentry permit age (if have one) 

 

Safest bet is photocopy every page and they can select what they want.

 

The OP is a bit vague.

Do you mean you have a new passport and you're moving your visa over from the old one?

My new UK passport is on its way back to me and I would like to know the answer to your question, if it's what I think it is.

11 minutes ago, 2long said:

The OP is a bit vague.

Do you mean you have a new passport and you're moving your visa over from the old one?

My new UK passport is on its way back to me and I would like to know the answer to your question, if it's what I think it is.

Yes correct, have a new passport and moving the visa over from the old one to new one. 

39 minutes ago, 2long said:

The OP is a bit vague.

Do you mean you have a new passport and you're moving your visa over from the old one?

My new UK passport is on its way back to me and I would like to know the answer to your question, if it's what I think it is.

Attached is the current requirements from Bangkok's immigration office.

 

However, your local immigration office may do things a little differently...

 

For example, I transferred my extension stamps to my new British passport earlier this year at the Chiang Mai office.

But I didn't need a certificate from the embassy and the application form was completely different  from the Bangkok one.

 

 

Did this at CW a couple of days ago. The girl on the information desk told me to copy every page, but it didn't feel necessary so I asked again in L section and they said just arrival stamp, non o visa page, and latest extension. When I went to the copy place downstairs turned out she was very familiar with knowing what was required and at locating these pages in the old passport for stamp transfer.