All aliens working in Thailand must hold a valid work permit, issued by the Department of Employment of the Ministry of Labor and Social Welfare pursuant to the Alien Employment Act B.E. 2521 (A.D. 1978). "Work" is broad, covering physical and mental activities, whether or not for wages or other remuneration. Working without a valid work permit even for a day is a criminal offense or for charity or NGO's with no exceptions. The validity period of a work permit is governed by the holder's immigration status, i.e. a work permit usually expires on the last day of the period of stay allowed by immigration officials as shown on the alien's visa. Aliens holding transit and tourist visas are not permitted to work. 
Advice: Apply for a Work Permit so you can work legally in Thailand & now since June 6th you must have a  work permit to open a bank account. Remember you must now be registered for VAT so some law services may not include tax or government fees in their prices.

WORK PERMITS:
Exemption: diplomatic staff, consuls, UN, working for Kingdom, if allowed by the government, if coming to enhance education, culture, sport, or arts or any other prescribed by Royal decree.
You must apply for a work permit if coming here to stay & work. Employer can file on workers behalf. Permit is valid only for duration time. You can process your non immigrant visa before you arrive in Thailand but then you need a work permit. The work permit must be renewed on a yearly basis. To obtain a work permit you need: alien residence book; passport with non immigrant visa. Local doctors certificate; Cert of employment, 3 photos, letter of transfer if from one job to another with foreign company. Education certs & any other relevant documents. You can only work on what the permit says & allows you to do. It helps to submit copies of all business tax returns, balance sheets etc. They say an expat earns around 65,000 baht a month unless he receives other benefits like housing etc. Plus if he is the Director. But if you are a director and your Thai partner is the main director then the salary will generally be less. Note every company is different so what they may say is needed by one is always different from another.
 If wanting to open a Bank account in Thailand Thai farmers require passport whereas Krung Thai want to see a work permit.  Cost for work permit depends on the lawyer but look at between anywhere up to 15,000 baht for processing your work permit. Make sure this includes govt fees & tax ID. We charge 12,000 baht but in Bangkok expect to pay more even up to 20,000 baht.  Obtain a letter from the immigration dept. Take passport & 2 photos to the immigration & they will write this letter for you. No charge (although we have been told they are now charging 200 baht-500 baht? for the letter at various Immigration Offices). We can assist you.

WHAT YOU NOW NEED:

The first step is to have a non immigrant B visa & to obtain you must go to a Thai Embassy say in Penang. Malaysia etc. Do not go to Vientiane as they do not allow multiple visas. Write to us [ Non immigrant visas ] & we will tell you how to go about all this. You can obtain a non immigrant visa from your home country BUT you must have a letter from a Thai Company willing to employ you on letterhead & company stamp & some places eg. Penang need your company papers. You can now transfer from say an "O" non immigrant visa & use this up until expiry date if you want a new work permit. Once finished then you must apply for a "B" non immigrant visa to keep your work permit alive.

1. Passport must have a valid Non-Immigrant visa Category "B".
2. Copy of Educational certificates OR Curriculum Vitae/Resume.
3. Three (3) photos, 2 * x 3 inch, front view, well dressed, head uncovered, taken not more than 6 months prior to filing of application; from shoulders up.
4. Certificate from a first class physician stating that applicant is not a person of unsound mind. Costs 150 - 400 Baht at a Thai hospital.
5. Home address in Thailand & your Office needs to be an Office if a new company. The Labour Office will inspect so you need to have a map of your Office with streets; a work breakdown of all your employees and job situation on a tree type work system for your company. Remember 1 work permit you must employ 4 Thai workers.
6. Photo of your Office
7. Must register for VAT (Por Por 01, Por Por 20).
8. Your company must be in operation less than 60 days after formation otherwise you need to do the company process again to have your company re-dated before you apply for your work permit. Therefore you must have a copy of the balance sheet for the company.
9. As said you now need to be registered for VAT. You also need to declare VAT for 1 year & VAT cert.
10. Map of Office & Employee work plan.
11. Letter from Director saying you need a foreigner in your company & job description that a Thai isn't employed instead.
12. If married to a Thai, marriage papers, ID card & house reg copies.
13. If using someone else to process then they must fill in the required authorization form and that person must supply copy of ID, house reg.10 baht
14. Your Office may be inspected for compliance.

Documents from the Employer (or your Thai Company if you are owner):

1. Employment certificate from company stating position; monthly salary.
2. Job description.
3. Organization chart giving names and positions of all employees of company. Indicate total number of Thais and Foreign employees in the bottom of the organization chart (Ratio is normally 4 Thais:1 Foreigner with minimum share registration of 2m baht; for 2 foreigners the share registration must be a figure between 4m baht).
4. Copy of company's list of Shareholders certified by the Commercial Registration Department, Ministry of Commerce.
5. Registration documents of company form and certified by the Commercial Registration Department, showing business classification, names of partners, Board of Directors, Committee, and Manager. Also acquire the List of Objectives of the Business.
6. Map of the company location.
7. Copy of VAT Certificate (Phor.Phor.20) / application for VAT registration (Phor.Phor.01)
8. Copy of Balance Sheet of previous year & financial statements plus bank statements
9. Certificate of registration Partnership/Co., Ltd.
10. Factory license (if Factory)
11. Evidence of Registered capital (not necessary paid up capital) of minimum 2,000,000 Baht per Work permit in the company.
12. Evidence of 5m baht tax over the past 3 years
13. The work permit can take about 2-4 weeks to process
14. Foreigners must pay monthly tax on salaries received and tax paid, married foreigners min 40,000 baht

The news laws affect: new & replacement work permits, reentry stamps on existing permits as well

HOW THE WORK PERMIT BOOK WORKS:

Once you receive your work permit you are bound to only do what the job role is in your blue book. This can apply to your place of work as well. You must renew in accordance with your B visa. If you are on a multiple visa & say the date of expiry is 20th August you should renew your visa before that date then take your Work permit book to the Labour office on the exact day the work permit expires 20th August--not before & not later as you can be fined. If say you decide to leave Thailand for a few weeks then make sure you take your work permit book back to the Labour Office, explain that you are leaving and they will make a record that you wish to renew your work permit when you return. If you do not then you must apply again for a new work permit. Our lawyer can help you if you have problems. If renewing your entry take your work permit book to the border as immigration may ask to see it. Most times they do not-- but better to be safe. Cost to renew at the moment is 300 baht. You need copies of your passport main page & last visa page. You will need to fill out a new form as well. Normally they may update same day or they you will have to go back in a couple of days to pickup your book and uplift another renewal form if you need the employer to sign next time. That's it till the next time.