"Work Permit Quotas and Capital Requirements: What a Thai Company Employing Foreign Staff Actually Has to Meet"

DeeMED's Non-Immigrant B guide states the headline numbers most foreign business owners in Thailand already know: 2 million THB in registered capital per foreign employee, and a 4-to-1 ratio of Thai to foreign staff. Both figures are real and both are still current, but they come from a specific regulatory source, they are calculated in a specific way, and they interact with BOI promotion and a separate restricted-occupations list in ways that matter once a company is actually trying to keep a work permit valid year over year rather than just obtain one.

Where the 2 Million Baht and 4:1 Figures Actually Come From

The underlying authority is the Alien Working Act B.E. 2551 (2008), later folded into the Royal Ordinance on the Management of Foreign Workers' Employment B.E. 2560 (2017), which took effect June 23, 2017 and consolidated several overlapping foreign-employment laws without changing the core capital and ratio concepts. The specific numeric thresholds, though, sit in the implementing ministerial regulations issued under that framework, most recently restated in the Department of Employment's criteria for considering work permit applications (the regulation was reissued and updated again in 2025, B.E. 2568, without altering the base figures). Under that framework, a Thai company sponsoring a foreign employee's work permit must show at least 2 million THB in fully paid-up registered capital for each foreign worker it employs, and must maintain a ratio of at least four Thai employees for every one foreign employee. Companies bringing capital in from abroad to establish a Thai branch or representative office face a related but distinct threshold, commonly cited at 3 million THB brought into the country, reflecting the different risk profile regulators assign to inbound branch capital versus a locally incorporated entity's registered capital.

How the Ratio Is Actually Calculated

The 4:1 ratio is not a one-time company-wide box to check; it is assessed at the point each new work permit application is filed and again at renewal, based on the company's current headcount and current registered capital, not the headcount at incorporation. A company that registers with 8 million THB in paid-up capital can support up to four foreign employees on the capital test, but each of those four work permits still needs the company to be able to demonstrate four Thai employees genuinely on payroll (with actual social security contributions, not names added shortly before an application) for every foreign employee it is sponsoring. In practice this means a company planning to bring on a fifth foreign hire needs to either raise registered capital by another 2 million THB, add four more verifiable Thai staff, or qualify for one of the exemptions described below, whichever is more realistic for the business.

What a Company Has to Show at Each Renewal, Not Just at First Application

Work permits in Thailand are typically issued for periods tied to the underlying Non-B visa extension, commonly renewed annually, and the capital and ratio tests are not a one-time hurdle cleared at the first approval. At each renewal, the Department of Employment expects to see the company's current company affidavit (reflecting registered and paid-up capital as it stands, not as it stood at formation), a current list of Thai employees with social security fund (Section 33) contribution records proving the 4:1 ratio is being maintained in practice, the company's most recent VAT filings (Por Por 30) and withholding tax filings showing the business has real ongoing operations and payroll rather than dormant activity, and the foreign employee's own tax filings (Por Ngor Dor 91) showing salary consistent with what was declared in the original work permit application. A company that let its Thai headcount slip below the 4:1 threshold, or that shows minimal VAT activity suggesting the business isn't genuinely trading, risks a renewal being questioned or delayed even if the original application cleared without issue.

How the BOI Exemption Actually Works

Board of Investment promotion changes this calculus at the legal root rather than just adjusting the numbers. Companies holding BOI promotion certificates operate under a separate legal channel: BOI-promoted businesses are exempted from the standard Alien Working Act ratio and capital tests specifically because BOI approval already functions as the government's assessment of the business's legitimacy and its genuine need for foreign expertise, so the ministerial regulations that impose the 2 million THB and 4:1 tests on ordinary companies carve out promoted entities rather than requiring them to separately prove the same thing twice. In practice, a BOI-promoted company sponsoring a foreign employee's work permit goes through the BOI's One-Stop Service Center, where the promotion certificate itself substitutes for the capital and ratio documentation an ordinary company would otherwise need to assemble, and processing tends to be faster as a direct result. Regional operating headquarters, regional offices, and representative offices registered under their own specific frameworks receive comparable, though not identical, treatment, reflecting that these entity types are, by design, foreign-capital-heavy and not expected to build a large Thai headcount the way an ordinary trading or manufacturing company would.

The Restricted Occupations List

Separately from the capital and ratio tests, the Alien Working Act framework maintains a list of occupations reserved exclusively for Thai nationals, regardless of a company's capital or ratio compliance. The list originated at 39 occupations under the Working of Aliens Act B.E. 2521 (1978) and was substantially trimmed by the Reserved Occupations Regulation of 2022 (Royal Gazette, February 3, 2022), which cut the list to a shorter set of roles concentrated in traditional crafts and specific manual trades: work such as hand-weaving, mat and basket making from reed or bamboo, Thai musical instrument making, niello and lacquerware work, and several categories of skilled manual and artisanal labor, alongside longstanding restrictions on tour guiding, and certain licensed professions such as legal practice and accountancy where Thai professional licensing bodies impose their own nationality requirements independent of the Alien Working Act. This is relevant to foreign professionals and investors specifically because the restricted list operates independently of whether someone is a company director, a majority shareholder, or otherwise senior in the business; holding equity or a director title does not create an exemption for actually performing one of the reserved occupations personally, so a foreign investor whose day-to-day role brushes up against a licensed profession (accounting, legal work, or a listed trade) needs the company structured so that role is performed by Thai-licensed staff, with the foreign principal's own work permit application scoped to management, technical, or advisory functions rather than the restricted activity itself.

Why This Matters Beyond the First Work Permit

None of this is a one-time compliance exercise. A company that grows its foreign headcount without proportionally growing paid-up capital or Thai staff will find its next work permit application, or its next renewal, harder to clear even if its first one went smoothly, and a company whose actual VAT and payroll filings don't support the numbers on paper faces the same exposure. Getting the capital structure, ratio, and BOI-eligibility question right before the second or third foreign hire, not after an application gets stuck, is the difference between a predictable hiring plan and a scramble.

DeeMED's Visa & Immigration services help foreign-owned Thai companies structure registered capital, Thai headcount, and BOI eligibility correctly from the first work permit application through every subsequent renewal, so growth in foreign staffing doesn't outpace what the company can actually document.