I was there lat Monday an had some idl time on y hanfd ds and actually read the bulletin board. I noticed a to new passports there wer ome rules that neede to be followed. Now I guy I'm working off memory here so please check if for yourself. When renewing your passprt, they want the annual vias from the old passport retained and would be more happy with the actual passport. Along with a letter from your embassy that the new passport is in fact valid.

I have five years left on mine so not hardly in a hurry, hope I remember to check that again, when the time is near.

Remember guys from memory, check this for yourself, don't go buy dusty cob webs

Ray,I renewed my passport a few years ago.If I remeber right,I had to take the old passport with its punched out holes to immigration.They transferred the visas and made the proper notations into the new passport!

I changed mine last month. Sent the old one off with the form from the internet and signed photo's to the British Embassy. They returned new and old passport in about 3 weeks.
Went to Nong Khia and it the immigration office, guy filled out a change of passport form which I signed and the new one was noted with the relevant information on the first page.
No letter required.
The only thing is that on the website they state that if the old passport is damaged in some way they will not return it and that would not be good if your visa is in it.
Ps They also made a careful note of any VOA's in the last six month's in the new passport, so renewing a passport is not a way around that.

Thanks guys, so I take it the Embassy is aware of this and it shouldbn't be a problem.

I like those T's crossed and the I's dotted

The US Embassy gives you a letter when they issue a new passport. Imperative to present your newly expired passport to Immigration so that they can transfer the visas and so forth to the new passport.

I did this two weeks ago arriving in Bangkok with new and old passport.
They transferred extension and re-entry permit. No document from my embassy was required, just a form and copies of passport pages.

It was a strange procedure at soi Suan Phlu tough.