What must a Thailand business visa invitation letter include?

Company name and address, company registration number, date, applicant's full name (matching passport exactly), passport number, nationality, job title, purpose of employment, intended start date and duration, a declaration of responsibility, director's signature with printed name and title, and the company seal in blue ink.

What is the Por Por 20 and why does immigration ask for it?

The Por Por 20 is the company's VAT registration certificate issued by the Revenue Department. It verifies the company is operating as a registered business. Most consulates require it alongside the invitation letter. Many applicants have never heard of it until mid-application ask your employer's HR or accounts team well in advance.

Does the invitation letter need to be notarised?

Not always requirements vary by consulate. Some consulates require notarisation, particularly for applications from outside Thailand. Check the specific requirements of the consulate you are applying to before finalising the letter.

Thailand Business Visa Invitation Letter 2026

The invitation letter makes or breaks a Non-B visa application. Get it right and the rest falls into place. Get it wrong and you are starting over typically weeks later after your employer has redone the documentation.

Overview Invitation Letter

Who Issues the Invitation Letter?

The letter must come from a company or organisation registered in Thailand, written on their letterhead and signed by an authorised director. A foreign company without Thai registration cannot issue a Thai Non-B visa invitation letter they must have a Thai subsidiary, branch office, or representative office.

Foreign company without Thai registration? A letter on foreign company letterhead without a Thai registration number will not be accepted. If your employer is foreign-based, they need a Thai-registered entity to issue the letter.

Mandatory Elements

Company name in Thai and English, and official Thai address
Company registration number (เลขทะเบียนนิติบุคคล)
Date of letter (must be recent typically within 3 months of the visa application)
Applicant's full name exactly as in their passport
Applicant's passport number
Applicant's nationality
Job title or position
Purpose of employment or visit
Intended start date and duration
Declaration that the company confirms the invitation and takes responsibility
Signature of authorised director with printed name and title
Official company stamp (blue ink seal)

Company Documents Required Alongside the Letter

Affidavit of company registration (หนังสือรับรอง) from the Department of Business Development, within 6 months
List of shareholders
VAT registration certificate (Por Por 20) issued by the Revenue Department
Company financial statements (in some cases)

The Por Por 20 is the one people miss. Ask your employer's HR or accounts team for this well in advance it is issued by the Revenue Department and your company's accounts department should have a current copy. Applications without it are returned.

Sample Letter Structure

[Company Letterhead with logo, address, registration number]

Date: [Date within 3 months of application]

To: The Royal Thai Consulate General, [City]

Subject: Letter of Invitation for Non-Immigrant Visa (Category B) for [Applicant Full Name]

Dear Sir or Madam,

On behalf of [Company Name] (Company Registration No. [xxxxxxxxxx]), registered at [Full Thai Address], we hereby confirm that we have invited [Applicant Full Name] (Passport No. [xxxxxxxxxx], Nationality: [Country]) to join our company as [Job Title] commencing [Start Date].

The purpose of this invitation is for [applicant name] to [description of role and responsibilities]. Their expected period of employment is [duration]. All expenses relating to [applicant name]'s stay in Thailand will be the responsibility of [Company Name].

We respectfully request that you grant [applicant name] a Non-Immigrant B visa to enable them to fulfil this role. Please do not hesitate to contact us if you require further information.

Yours faithfully,
[Director's Signature and Printed Name]
[Title]
[Company Name]
[Company Seal]

This is a template guide only. Consulate requirements vary. Always check the current requirements of your specific Thai consulate before finalising the letter.

Common Rejection Reasons

Company registration number missing or incorrect
Letter dated more than 3 months ago
Applicant name in the letter does not exactly match the passport
No company seal or stamp
Letter signed by someone not listed as authorised director in the company affidavit
Vague job description that does not explain why a foreign national is needed
Por Por 20 not provided alongside the letter

Frequently Asked Questions

Can a foreign company issue the invitation letter?

Only if they have a Thai-registered entity (subsidiary, branch office, or representative office). A letter on foreign company letterhead without a Thai registration number will not be accepted at a Thai consulate.

What is the Por Por 20?

The company's VAT registration certificate issued by the Revenue Department. It proves the company is a registered operating business. Most consulates require it alongside the invitation letter. Ask your employer's accounts team for a current copy it is commonly overlooked until mid-application.

Who Issues the Invitation Letter?

Mandatory Elements

Company Documents Required Alongside the Letter

Sample Letter Structure

Common Rejection Reasons

Frequently Asked Questions

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