my son was born in the uk & i am a uk citizen but we are now living in thailand for the next year or so with his thai father. we are not married & his fathers name is not on the birth certificate. what are my options for getting him a passport???

For starters, you would need the Thailand Embassy in London to somehow issue a Thai birth certificate with the Thai father listed (acknowledged) thus officially establishing your son's Thai nationality. After registering the Thai birth the embassy could issue a Thai passport. You didn't say how old your son is?

Edited June 18, 201016 yr by InterestedObserver

"You didn't say how old your son is? ""

I would think if its "a Baby", can be up to 1 year or a bit more.

my son is one year four months....... thanks for the info...

As said, you need to register the birth at the Royal Thai Embassy in London. You will need the Thai father's cooperation. They can then issue your son with a Thai passport.