what is the longest extension of stay you can get at immigration with a visa exempt entry (30-days)? Is it only 7 days? or is it up to the discression of immigration? I am looking to extend for 2.5 weeks on a 30-day entry. I have a doctors appointment, but wasn't sure how set in stone the 7 days extension was. i would rather not drive to cambodia tomorrow.

7 days is it!

Immigration can grant a 90 day extension for medical reasons provided you have a letter from a Thai hospital doctor providing said treatment.

60 day extension if you have a Thai wife.

This is for all visas and a Visa Exemption.

is it a YMMV thing, so I should go to immigration with what I have and go from there?

My thai girlfriend is actually preagant, and I have a doctors appointment for my high blood pressure.

Taken from Police Order 777/2551.

2.25 In the case of medical

treatment or convalescence or to look after a patient:

Permission will be granted for a period of not more than 90 days at a time.

(1) Confirmation and request has been made by a physician

responsible for the treatment. The Physician must describe the details of treatment and advised that the illness is a barrier for travelling.

(2) In the case of looking after a patient, confirmation and request has been made by the physician responsible for the treatment or by an embassy or consulate.

(3) Patient Carer, except parents, spouse, children, adopted children or children of spouse, shall be granted no more than 1 extra person.

"My thai girlfriend is actually preagant, and I have a doctors appointment for my high blood pressure."

Is one the cause of the other?

Not sure an appointment is a good enough reason for imm to give you a medical extension.

Marry the girl and get a 60 day extension.