SSF caps. PIT brackets. BOI incentives. Thailand payroll, owned.
Thailand’s payroll is not a configuration exercise. It demands a live SSF contribution engine with salary caps, progressive PIT withholding across seven brackets, BOI-promoted company tax incentives, provident fund integration, and in-country people with direct authority relationships. Most providers deliver two of these. Mercans delivers all of them – on a single proprietary stack with no intermediaries.
native payroll
vs nearest peer
since inception
- Employer SSF
- 5% (cap THB 17,500)
- Employee SSF
- 5% (cap THB 17,500)
- SSF Max Contribution
- THB 875/month each (effective Jan 2026)
- Workmen’s Comp.
- 0.2%–1.0% ER only
- PIT Rate
- 5%–35% progressive
- PIT Brackets
- 7 bands · 0–5M+ THB
- Provident Fund
- Voluntary · 2%–15%
- Severance Max
- 400 days (20+ yrs)
- Overtime Standard
- 150% hourly rate
- Overtime Holiday
- 300% hourly rate
- Min. Wage (Bangkok)
- THB 400/day (2025)
- 13th Month
- Not mandatory
- WHT Contractors
- 1%–5% per service type
- PDPA
- Active since Jun 2022
- Pay Cycle
- Monthly · THB only
Payroll compliance: the details that can’t be missed
Thailand’s regulators don’t grade on a curve. The SSO levies retroactive assessments on under-reported contributions. The Revenue Department enforces PIT withholding accuracy through employer audits with surcharges up to 200%. Labour courts award substantial severance for wrongful termination. The PDPA imposes personal data fines up to THB 5 million. None of these failures announce themselves – they accumulate silently until an audit makes them very visible.
SSF retroactive shortfall + surcharges
Under-reported SSF contributions on allowances or bonuses are retroactively assessable with 2% monthly surcharges on outstanding amounts per the Social Security Act.
PIT withholding error – Revenue Dept audit
Incorrect monthly withholding, wrong bracket application, or missed deductions trigger Revenue Department assessments with surcharges of 1.5% per month plus potential penalties up to 200% of the underpayment.
Severance miscalculation – Labour Court
Thailand’s Labour Protection Act mandates tiered severance up to 400 days’ wages for 20+ years of service. Miscalculated final settlements are the most common trigger for Thai Labour Court disputes.
PDPA non-compliance = THB 5M+ exposure
Thailand’s PDPA (effective June 2022) imposes administrative fines up to THB 5 million and criminal penalties for mishandling employee personal data. Payroll processors are directly liable as data processors.
The three types of providers who struggle with Thailand
Global Aggregator Platforms
Platforms like Deel, Remote, and Rippling operate through a partner network in Thailand — they don’t own the entity, don’t directly manage SSO filings, and don’t control the compliance relationship. When regulations change, the instruction travels: platform → partner → your payroll. Each handoff introduces delay and interpretation risk.
- ×No direct SSO relationship — third-party intermediary handles filings
- ×PIT withholding often simplified or approximated
- ×Provident fund administration absent or outsourced
- ×BOI-promoted company incentives not natively supported
Large Global Payroll Incumbents
ADP, Ceridian, and similar incumbents have Thailand coverage — in name. In practice, their APAC coverage is often delivered through regional partners or legacy systems that weren’t built for Thailand’s SSF cap structure, seven-bracket PIT system, or provident fund integration requirements.
- ×SSF cap calculations sometimes applied incorrectly on variable pay
- ×Provincial minimum wage tracking manual or incomplete
- ×Long implementation timelines — Thailand not a core market
- ×No Thai-language payslip generation in-platform
Local Thai Firms
Local Thai accounting and tax firms know the market — but they can’t scale with you. No payroll technology platform, no HCM integration, no multi-country consolidation, and no data security certifications that multinationals require. Fine for 15 employees. Inadequate at 150.
- ×No proprietary payroll technology — manual spreadsheet-based processing
- ×No HCM connector — Workday, SAP, Oracle feeds require custom work
- ×No data security certifications (SOC 1/2, ISO 27701, BCR)
- ×No APAC consolidation — cannot report across Thailand + other markets
The only provider that closes every gap
Mercans is the only Thailand payroll provider that combines a proprietary payroll technology stack, full-time in-country compliance teams, direct authority relationships, and enterprise-grade data security – simultaneously, on one contract, with no intermediaries.
The only engine built for Thailand’s actual payroll architecture
G2N Nova™ is the world’s only API-first gross-to-net payroll engine. It natively models Thailand’s SSF contribution with the THB 17,500 salary cap, handles seven-bracket PIT progressive withholding with mid-year joiner annualisation, enforces provincial minimum wage compliance, and auto-generates SSO and Revenue Department reporting outputs. This isn’t configuration. It’s engineering.
Full-time Thailand team – not a partner you phone when things break
Mercans employs full-time payroll and compliance professionals in Thailand. They maintain active relationships with the SSO, Revenue Department, and Department of Labour Protection – not through a contact directory, but through ongoing regulatory engagement. When the SSO adjusts contribution rules, when the Revenue Department updates withholding tables, when minimum wages are revised – we know before it reaches your inbox.
The security posture multinationals require – and Thailand now mandates
Thailand’s PDPA (Personal Data Protection Act, effective June 2022) requires payroll processors handling employee personal data to maintain documented privacy controls and data processing agreements. Mercans holds BCR approval, ISO 27701 certification, SOC 1 & 2 certifications, and ISO 27017/27018 – the only payroll provider in APAC with this complete certification stack. Zero security breaches since inception.
Where Mercans wins on every Thailand-specific capability
Each row is a Thailand-specific capability. Each cell shows native coverage as a fill bar – full = native in-platform, half = partial / manual workaround, empty = gap.
Thailand Capability Coverage · 11 dimensions
ER 5% + EE 5%
Tax holidays · reduced rates
Workday · SAP · Oracle
Every rate. Every cap. Every obligation.
Thailand payroll operates on exact numbers with hard deadlines. Mercans builds every figure below into G2N Nova™ and monitors them proactively – so you’re never discovering a rate change from a penalty notice.
Thailand · Rate & Compliance Dashboard
Live 2025–26SSF Cap Creates a Fixed Maximum – Not a Percentage Ceiling
The THB 17,500 salary cap means the maximum SSF contribution is THB 875/month per side (ER and EE). For employees earning above THB 17,500, the contribution is flat – not 5% of actual salary. Applying 5% to full salary is over-deduction. G2N Nova™ enforces the cap automatically.
→ Modelled natively in G2N Nova™PIT Year-End Reconciliation Can Create Large Adjustments
Thailand’s monthly PIT withholding is an estimate based on annualised income. The final tax liability is determined on the annual return (PND 91). Bonuses, irregular payments, and mid-year salary changes can create significant year-end over/under-withholding that must be reconciled.
→ Full annualisation + year-end reconciliation in G2N Nova™Severance Tiers Were Extended to 400 Days in 2019
The Labour Protection Act (No. 7) B.E. 2562 (2019) added a seventh severance tier: 400 days’ wages for employees with 20+ years of continuous service. Companies using pre-2019 severance tables are under-provisioning terminal liabilities and face Labour Court exposure.
→ All 7 severance tiers modelled with scenario logicPDPA Compliance Is a Payroll Processor Obligation
Thailand’s PDPA places explicit obligations on data processors, including payroll service providers. Non-compliant processors create direct liability for employer clients. Administrative fines up to THB 5 million, criminal penalties up to one year imprisonment, and punitive damages up to twice actual damages.
→ BCR · ISO 27701 · PDPA agreements standardRun a Thailand payroll. Right here, right now.
Switch workforce type. Move the sliders. Every number you see is the same calculation G2N Nova™ runs in production – SSF cap logic, PIT progressive withholding, provident fund deductions, and true cost of employment exposed live.
Thailand Payroll Sample · Live
G2N Nova™ engineEight things only Thailand experts know to handle
These are the compliance details that don’t appear in standard payroll setup guides – but appear in every SSO audit, Revenue Department inspection, and Labour Court case we’ve encountered in Thailand over 15 years.
SSF Cap Means Fixed Maximum, Not Percentage Ceiling
The SSF salary cap of THB 17,500 means the maximum monthly contribution is THB 875 per side (employer and employee). For workers earning above THB 17,500/month, applying 5% to actual salary is systematic over-deduction. The cap applies to gross monthly wages including most allowances.
Seven PIT Brackets with Complex Deduction Rules
Thailand’s PIT uses seven progressive brackets (5%, 10%, 15%, 20%, 25%, 30%, 35%) with numerous deduction categories: personal allowance (THB 60,000), spouse, children, SSF, provident fund, life insurance, home mortgage interest, and donations. Each deduction has its own cap and eligibility rules.
Provident Fund Is Voluntary but Creates Lock-In Obligations
Once established, a provident fund creates ongoing employer matching obligations (2%–15%). Fund rules, vesting schedules, and withdrawal conditions are governed by the Provident Fund Act and the specific fund committee. Employers cannot unilaterally reduce contributions or dissolve the fund without member consent.
Seven Severance Tiers Including 400-Day Maximum
The 2019 amendment added a seventh tier: 400 days’ wages for 20+ years of service. The full tiers are: 30d (120d–1yr), 90d (1–3yr), 180d (3–6yr), 240d (6–10yr), 300d (10–15yr), 360d (15–20yr), 400d (20yr+). Special notice pay and business closure rules add further complexity.
BOI-Promoted Companies Have Different Tax Treatment
Companies promoted by the Board of Investment (BOI) can receive corporate tax holidays, reduced tax rates, and exemptions from import duties. Employees of BOI-promoted companies may have different withholding treatment for BOI-exempt income streams. Payroll must segregate BOI and non-BOI income correctly.
Overtime Rates Vary by Day Type and Cannot Be Waived
Standard overtime is 150%, holiday overtime is 300% of hourly rate, and holiday work (non-overtime) is 100% additional. Management-level employees may be exempt from overtime but not from holiday premium pay. Overtime caps at 36 hours/week. These rights cannot be waived by contract.
Contractor WHT Rates Vary by Service Type
Withholding tax on service payments to contractors varies: 1% for transport, 2% for advertising, 3% for professional services, 5% for rental payments. Each service type has a different WHT rate and different filing requirements (PND 3 for Thai residents, PND 53 for companies). Most platforms apply a single flat rate.
Expat Workers Face Dual Tax + Work Permit Dependencies
Foreign workers in Thailand need a Non-Immigrant B visa and work permit, which must be renewed annually. Work permit holders are tax residents from Day 1 and subject to PIT on Thailand-sourced income. Since 2024, worldwide income remitted to Thailand is also taxable. Work permit revocation triggers immediate employment termination.
One workforce. Two entirely different compliance tracks.
The foundational split in Thailand payroll – Thai nationals on full SSF vs. expatriate workers on work permit-linked employment – is not a configuration toggle. It requires two distinct calculation engines, two sets of filing obligations, and two different terminal settlement frameworks. Mercans runs both simultaneously on every pay cycle.
Parallel Compliance Engines
SSF registration from Day 1. Employer 5% + Employee 5% on salary up to THB 17,500 (max THB 875/month each). Contributions cover sickness, maternity, disability, death, child allowance, old age, and unemployment.
PIT withholding requires monthly annualisation. Monthly income is annualised, deductions applied, progressive brackets calculated, then de-annualised to monthly withholding. Bonuses and irregular payments require separate annualisation treatment.
Provident fund creates matching obligations. If established, the employer matching rate (2%–15%) is a contractual commitment. Vesting schedules, withdrawal conditions, and fund committee governance add ongoing administration.
Severance exposure reaches 400 days. The 7-tier severance structure means long-tenured employees have substantial terminal entitlements. Accrual provisioning must reflect the correct tier based on continuous service.
Expats are tax residents from Day 1. Work permit holders pay PIT on all Thailand-sourced income from the first day of employment. Since 2024, worldwide income remitted to Thailand within the same tax year is also subject to Thai PIT.
SSF applies to expat employees equally. Foreign employees with work permits are enrolled in SSF on the same terms as Thai nationals. The THB 17,500 cap applies. Benefits include sickness, maternity, and old-age coverage.
Contractor WHT varies by service type. Independent contractors face withholding at 1%–5% depending on the service category. PND 3 (Thai resident) and PND 53 (company) filing requirements differ. Cross-border contractors may trigger treaty relief claims.
Work permit revocation = immediate termination. If a foreign employee’s work permit is revoked or not renewed, continued employment is illegal. The employer must terminate and settle all obligations including severance, prorated leave, and final tax reconciliation.
Every obligation. Every authority. Mercans owns the calendar.
Thailand compliance runs across SSO, Revenue Department, and the Department of Labour Protection on monthly, annual, and event-triggered cadences. Mercans’ managed payroll absorbs every filing as standard scope – you don’t track deadlines. We do.
SSF Contribution Remittance
Employer and employee SSF contributions (5% + 5%, cap THB 17,500) plus Workmen’s Compensation Fund remitted for all enrolled employees. SSO cross-references contributions against headcount records.
PND 1 – PIT Withholding Remittance
All employee PIT withholdings remitted via e-filing by the 7th of the following month (15th for e-filing). Late remittance triggers 1.5% monthly surcharge plus potential 200% penalty on underpayment.
PND 3/53 – WHT on Service Payments
Withholding tax on contractor and vendor service payments filed monthly. PND 3 for payments to Thai individuals, PND 53 for payments to companies. Each service type has a different WHT rate (1%–5%).
PND 1 Kor – Annual Tax Summary
Annual summary of all PIT withholdings for all employees. Individual withholding certificates (50 Tavi) must be issued to employees by February 15. The PND 1 Kor is the primary Revenue Department reconciliation document.
SSO Registration & De-registration
New hires must be registered with SSO within 30 days. Terminating employees must be de-registered. SSO benefits (unemployment, sickness) continue for a specified period post-employment depending on contribution history.
Severance & Final Settlement
Tiered severance calculation (30–400 days per service tenure), prorated annual leave payment, and final PIT reconciliation. Severance is exempt from PIT up to THB 300,000. Amounts above are taxable.
Work Permit & Visa Renewal (Expats)
Foreign employee work permits require annual renewal. Non-B visa renewals must align with work permit validity. Revenue Department tax clearance may be required. Permit expiry without renewal triggers illegal employment status.
Corporate Income Tax & BOI Reporting
Half-year (PND 51) and annual (PND 50) corporate income tax returns. BOI-promoted companies must file separate reports on incentive utilisation. Transfer pricing documentation required for related-party transactions.
Thailand is one market. Mercans covers the entire region.
For companies running payroll across multiple APAC markets, complexity multiplies – not adds. Each country runs its own labour authority, social insurance body, and tax withholding regime. Mercans covers all major APAC markets on a single platform with country-specific compliance engines running in parallel.
covered
1 contract
consolidation
APAC
Every filing. Every format. Submission-ready.
Mercans generates the exact file types that SSO, the Revenue Department, and the Department of Labour Protection expect to receive — not formatted summaries that need reformatting before you can submit them.
