Many Japanese companies operating in Thailand assume that the standard 20% corporate income tax rate is unavoidable. In practice, however, Thailand offers a range of tax incentives specifically designed for small and medium-sized enterprises (SMEs) — incentives that often go unused simply because companies are unaware of them. This article provides a structured overview of the key SME tax incentives available in Thailand as of March 2026, so you can assess whether your Thai entity qualifies and identify which schemes are worth pursuing.
1. How Is an “SME” Defined in Thailand?
Thailand uses two distinct definitions of “SME” depending on the context. Understanding this distinction is critical before applying for any incentive.
Definition ①: OSMEP Definition (for Government Programs)
The Office of SME Promotion (OSMEP / สำนักงานส่งเสริมวิสาหกิจขนาดกลางและขนาดย่อม) manages Thailand’s SME policy. OSMEP certification is required to access certain programs such as government procurement preferences and the Big Brother scheme.
| Sector | Category | Employees | Annual Revenue |
|---|---|---|---|
| Manufacturing | Small | ≤ 50 | ≤ THB 50 million |
| Manufacturing | Medium | ≤ 200 | ≤ THB 500 million |
| Services / Wholesale / Retail | Small | ≤ 30 | ≤ THB 50 million |
| Services / Wholesale / Retail | Medium | ≤ 100 | ≤ THB 300 million |
Both the employee and revenue criteria must be satisfied simultaneously. The above reflects the 2025 revised standards — verify with OSMEP’s latest official publication.
Definition ②: Revenue Code Definition (for Tax Purposes)
For corporate income tax purposes, the Revenue Code defines an SME by two criteria only:
- Paid-up capital: THB 5 million or less
- Annual revenue: less than THB 30 million
Both conditions must be met. This definition is narrower than the OSMEP definition and applies specifically to the reduced tax rate and digital deduction schemes described below.
Can Japanese-Owned Entities Qualify?
Yes. Foreign-invested companies, including Japanese subsidiaries incorporated in Thailand, can qualify as Thai SMEs under both definitions if they meet the relevant criteria. There is no requirement for Thai majority ownership. However, the entity’s business activities may require separate consideration under the Foreign Business Act (FBA) (see: Thailand’s FBA Reform 2025).
2. Reduced Corporate Income Tax Rates for SMEs
Thailand’s standard corporate income tax rate is 20%. Entities meeting the Revenue Code’s SME criteria (paid-up capital ≤ THB 5 million + annual revenue < THB 30 million) are eligible for the following graduated rates:
| Taxable Income (Net Profit) | Tax Rate |
|---|---|
| THB 0 – 300,000 | 0% (tax-exempt) |
| THB 300,001 – 3,000,000 | 15% |
| Over THB 3,000,000 | 20% (standard rate) |
Calculation Example
Net profit of THB 2,000,000:
| Bracket | Amount | Rate | Tax |
|---|---|---|---|
| First THB 300,000 | THB 300,000 | 0% | THB 0 |
| THB 300,001 – 2,000,000 | THB 1,700,000 | 15% | THB 255,000 |
| Total | THB 2,000,000 | (Effective: 12.75%) | THB 255,000 |
Under the standard 20% rate: THB 2,000,000 × 20% = THB 400,000. The SME rate saves THB 145,000 (approximately JPY 640,000) per year in this example.
The zero-tax bracket and the 15% middle bracket represent a more favorable structure than, for instance, Japan’s reduced rate of 15% on corporate income up to JPY 8 million for small companies. In practice, some Thai subsidiaries that meet the SME criteria continue to file at the standard 20% rate simply because the eligibility was not checked — a straightforward and worthwhile item to review.
3. Quick Big Win: A THB 32.7 Billion SME Support Package
In November 2025, the Thai government announced the “Quick Big Win” policy package for SMEs, approved by Cabinet in December 2025. The package totals THB 32.7 billion and includes several distinct components.
① Accelerated Tax Refunds
The Revenue Department is fast-tracking corporate income tax refunds for 20,000 SMEs, totaling THB 60 billion in accumulated refunds. The target completion date is end of 2026. If your Thai entity has filed for a tax refund that remains outstanding, this is a good time to follow up with the Revenue Department.
② Big Brother Helps Little Brother Scheme
This scheme creates a tax incentive for large companies to integrate SMEs into their supply chains:
- Large companies that place orders with or provide support to SMEs may claim a deduction of 1.5x to 2x the amount paid to the SME
- SMEs involved receive digital transformation support (e.g., e-Tax Invoice adoption)
- Approximately 1,500 SMEs are expected to participate, with an estimated THB 1.7 billion in annual tax refund acceleration
Relevance to Japanese companies:
- Japanese multinationals with Thai operations sourcing from Thai SMEs may be able to access the enhanced deduction
- Japanese-owned Thai subsidiaries qualifying as SMEs may become beneficiaries of Big Brother support from larger partners
The exact conditions governing the 1.5x vs. 2x deduction rate should be confirmed against official publications from the Ministry of Finance or Revenue Department.
③ Government Procurement Preferences
OSMEP-certified SMEs receive a 5% price advantage in government procurement bids (subject to e-Tax Invoice usage). For Japanese entities exploring government-related business in Thailand, this is worth factoring into eligibility planning.
④ Credit Guarantee Expansion (SBCG)
The Small Business Credit Guarantee Corporation (SBCG) is providing THB 50 billion in guarantee capacity, with no guarantee fee for the first three years — a meaningful reduction in borrowing costs for qualifying entities.
4. Digital Investment Double Deduction (200%)
A Royal Decree provides a 200% deduction for qualifying digital software expenditure by Thai SMEs.
Key Details
| Item | Detail |
|---|---|
| Legal basis | Royal Decree (under Revenue Code) |
| Eligible period | June 24, 2025 – December 31, 2027 |
| Eligible entities | Thai-registered entities with paid-up capital ≤ THB 5M and annual revenue < THB 30M |
| Deduction | 200% of qualifying software cost (purchase, rental, or subscription) |
| Cap | THB 300,000 |
| Qualifying software | DEPA-registered software (accounting, ERP, CRM, POS, e-commerce platforms, etc.) |
Calculation Example
Annual ERP subscription cost of THB 150,000:
- Standard deduction: THB 150,000 (as a business expense)
- With double deduction: THB 300,000 (THB 150,000 × 200%) — the cap of THB 300,000 is fully utilized
- Additional deduction of THB 150,000; at a 15% tax rate, this represents a THB 22,500 saving
Important Limitation
Entities receiving BOI investment promotion, benefits under the National Competitiveness Enhancement Act (NCEA), or the EEC Law are NOT eligible for this deduction. Companies with BOI tax exemption cannot stack this benefit on top. Verify the DEPA-registered software list before making purchasing decisions, as the list may change.
5. BOI Incentives for SMEs
BOI (Board of Investment) offers investment promotion incentives to qualifying SMEs, potentially including corporate income tax exemptions for 3–8 years and the option of 100% foreign ownership under certain schemes.
However, as noted above, BOI incentives and the digital investment double deduction cannot be combined. Whether BOI or the SME tax regime is more advantageous depends on the scale of projected profits, the level of digital investment, and the type of business activity.
Thailand also implemented BEPS Pillar 2 (global minimum tax, 15%) from January 2025, applicable to multinational groups with consolidated revenue exceeding EUR 750 million. Most SMEs will not be directly affected, but Japanese companies whose Thai subsidiary forms part of a larger group should consider whether the parent group’s BOI benefits may be subject to top-up tax. For a detailed overview of BOI incentives, see Thailand BOI New Rules 2025.
6. SME Tax Incentives That Japanese Companies Often Overlook
Based on the above, here are the four most commonly underutilized incentives:
① Reduced corporate income tax rate Check whether your Thai entity meets the SME criteria (paid-up capital ≤ THB 5M + revenue < THB 30M). If it does, confirm that the reduced graduated rates are being applied in your annual corporate income tax filing rather than the flat 20% rate.
② Accelerated tax refund (deadline: end of 2026) If your Thai entity has filed for a corporate tax refund that remains outstanding, the Quick Big Win initiative has created momentum for processing. Proactive follow-up with the Revenue Department may be worthwhile.
③ Digital investment 200% deduction (deadline: December 31, 2027) If your Thai entity subscribes to accounting software, ERP, CRM, or similar tools, check whether the software appears on DEPA’s registered list. If so, the deduction can be applied for qualifying expenditure up to THB 300,000 before December 2027.
④ OSMEP certification OSMEP certification unlocks government procurement advantages and may improve financing terms. If your Thai entity operates in a sector where government contracts are relevant, it is worth assessing eligibility.
Conclusion
Thailand’s SME tax landscape offers meaningful opportunities for Japanese-owned Thai entities — but navigating the overlapping definitions, eligibility criteria, and exclusions (particularly the BOI/double deduction conflict) requires careful analysis. Whether your Thai company qualifies as an SME, which incentives can be combined, and how these interact with your group’s overall tax position are questions best addressed with expert input.
We are available to advise on SME tax incentive eligibility, tax refund applications, and BOI strategy from both a Japanese and Thai law perspective — including an initial review of whether your Thai entity meets the SME thresholds. Please feel free to contact us.
This article is for general informational purposes about Thailand’s legal and tax system as of March 2026, and does not constitute legal advice under Thai law or tax advice. For specific tax matters, please consult a qualified tax professional. For Thai law matters, please consult a Thai-qualified legal professional. Our firm works in collaboration with JTJB International Lawyers’ Thai-qualified attorneys.