Prefix the fax number with Thailand country code (which is 66) and the area code.
Sending fax over the web is one of the most effective way to send fax documents abroad. In order for you to get the perfect provider, try to read reviews available online. Companies such as Ringcentral,freedomvoice and many others offer such service. you can start comparing the plans and pricing offered by these providers.
You dial a fax number exactly the same way you would dial the same number on a landline telephone at the same location.
The telephone country code for Thailand is +66, and you must omit the leading 0 from the Thai area code.
(The plus sign means "insert your international access prefix here." From a GSM mobile phone, you can enter the number in full international format, starting with the plus sign. The most common prefix is 00, but North America (USA, Canada, etc.) uses 011, Japan uses 010, Australia uses 0011, and many other countries use different prefixes.)
The country code and area code of Bangkok, Thailand is 66, (0)21.
The country code and area code of Chanthaburi, Thailand is 66, (0)39.
The country code and area code of Lampang, Thailand is 66, (0)54.
The country code and area code of Ratchaburi, Thailand is 66, (0)32.
The country code and area code of Saraburi, Thailand is 66, (0)36.
The country code and area code of Songkhla, Thailand is 66, (0)74.
The country code and area code of Trang, Thailand is 66, (0)75.
The country code and area code of Yala, Thailand is 66, (0)73.
The country code and area code of Chon Buri, Thailand is 66, (0)38.
The country code and area code of Ubon Ratchathani, Thailand is 66, (0)45.
The country code and area code of Khon Kaen, Thailand is 66, (0)43.
The country code and area code of Nahkon Sawan, Thailand is 66, (0)56.