Reviewed by ThaiLawOnline, a licensed Thai law firm practising in Thailand since 2006. Thai lawyer of record: Wichuda Atthamethakon, LL.M., Thai Bar Licence 3149/2556.
Last updated on September 5, 2026
4:1 ratio (อัตราส่วนพนักงานไทย 4 ต่อ 1, also written four-to-one ratio or 4 to 1 rule) is the requirement that a Thai company employ four Thai nationals for every foreigner it sponsors for a work permit and the matching one-year extension of stay. It travels with a second figure, 2,000,000 baht of paid-up registered capital per foreigner. Neither number is in the Foreigners’ Working Management Emergency Decree itself; both come from the criteria applied by the Department of Employment and the Immigration Bureau, which is why they are enforced at every renewal rather than only once.
Table of Contents
Where the rule comes from
The Department of Employment applies the ratio when it issues or renews a work permit for an ordinary company limited, and Immigration applies the same test when it grants the one-year extension of stay for business. The four Thai employees must be genuine: on the payroll, paid at least the provincial minimum wage, registered for social security and appearing on the monthly contribution form for the preceding months, typically three. Capital must be paid up, not merely registered, and each additional foreigner needs another 2,000,000 baht and another four Thais.
Halving applies where the foreigner is married to a Thai national: two Thai employees and 1,000,000 baht, for that spouse’s permit only. A company operating under the Treaty of Amity needs 3,000,000 baht. BOI-promoted companies do not have to meet the ratio at all, since the BOI approves their foreign positions directly.
What it costs and where companies go wrong
The real cost of a permit. Four Thai employees at the Bangkok minimum of 400 baht a day is 48,000 baht a month in wages plus the employer’s social security share, before any office or accounting cost. That figure, not the 3,000 baht government fee, is the price of a self-sponsored permit, and the self-sponsoring guide sets out how owner-managed companies plan for it.
Common mistakes. Counting part-time helpers, relatives or shareholders who draw no salary; letting a Thai employee leave shortly before renewal without a replacement on social security; and paying four salaries to people who never work. The last is the ghost employee, and it now sits inside the nominee enforcement described in the nominee crackdown guide: it invites a fraud allegation against the director, not just a refused permit. The documents that prove the ratio are the monthly social security form, the PND.1 withholding return and the employee list with copies of ID cards.
The numbers, and who is exempt
The standard rule and its variants are easiest read side by side.
| Situation | Thai employees per foreigner | Paid-up capital per foreigner |
|---|---|---|
| Ordinary Thai company limited | 4 | 2,000,000 baht |
| Foreigner married to a Thai national | 2 | 1,000,000 baht |
| Company under the Treaty of Amity | 4 | 3,000,000 baht |
| BOI-promoted company | No ratio | As approved by the BOI |
| LTR or SMART visa holder | Not applicable | Not applicable |
The ratio is a work permit rule, not a company law rule: a Thai company with no foreign staff may have as few employees as it likes. It also has nothing to do with the 51/49 shareholding split under the Foreign Business Act, though the two are often confused because both appear in the same company file at renewal.
Frequently asked questions
Do I need four Thai employees to get a work permit in Thailand?
For an ordinary Thai company limited, yes: four Thai employees on social security and 2,000,000 baht of paid-up capital for each foreigner sponsored. The requirement is checked at the first application and at every renewal by both the Department of Employment and Immigration.
Does BOI promotion remove the 4 to 1 ratio?
Yes. A BOI-promoted company does not have to meet the ratio, and its foreign positions are approved through the BOI with permits processed at the One Stop Service Centre. The exemption covers only positions the BOI has approved.
What is the ratio if I am married to a Thai?
The requirement is halved for that spouse’s own permit: two Thai employees and 1,000,000 baht of paid-up capital. Other foreigners in the same company still need the full four employees and 2,000,000 baht each.
See also: work permit, social security, registered and paid-up capital, BOI, and the guides on work permits in Bangkok and self-sponsoring a work permit.
Thai Law Updates, free by email
Plain-English updates on Thai law changes that affect foreigners: property, visas, marriage, business and wills. One short email a month from a firm practicing since 2006. No spam, unsubscribe anytime.