The reason I am asking is that I consider travelling to Singapore or Phillippines or Malaysia with a 19 years old unmarried Thai woman.

I know Thais under 20 require their parents consent to get a passport. So I was wondering if they can travel to asian visa free countries without their parents going too?

Yes, if they have a Thai passport

There will be no problems, my step son has a Thai Passport and we live in the UK, he went back to Thailand for a holiday when he was 17 alone and had no problems.

Andy

I know Thais under 20 require their parents consent to get a passport.

The age is 15 not 20.

No problem for her to travel with you at the age of 19.

I know Thais under 20 require their parents consent to get a passport.

The age is 15 not 20.

No problem for her to travel with you at the age of 19.

The age still seems to be 20:

e- Passport Application Requirements:

http://www.mfa.go.th/main/en/services/1415/21479-Requirements-for-the-Ordinary-e-Passports-Applicat.html

I know Thais under 20 require their parents consent to get a passport.

The age is 15 not 20.

No problem for her to travel with you at the age of 19.

The age still seems to be 20:

e- Passport Application Requirements:

http://www.mfa.go.th...s-Applicat.html

Definitely 20. Tried to get a passport for GF's 19 year old niece recently. Needed her mother's consent.

If she has a Passport already, yes. If not, look,that she gets a Passport.