How Our Payroll Team Runs Payroll for Foreign-Headquartered Companies in Thailand

If your headquarters is in Singapore, Hong Kong, the US, Australia, or Europe — and your Thai entity is a handful of engineers, a country manager, and maybe an admin — you don't have an accounting department in Bangkok. You probably don't want one. Hiring a Thai-speaking payroll officer who understands Revenue Department forms, Social Security Office filings, and the quirks of the Labour Protection Act is a 6-figure-baht annual cost just to clear the bar. And if they leave, the institutional knowledge walks out the door with them.

This is the problem our parent firm — one of Thailand's most experienced Tax Advisory / Audit (CPA) / Law firms, in Bangkok since 1996 and the official accountant of the American Chamber of Commerce in Thailand for over 10 years — has solved for foreign HQs since the late 1990s. The model is simple: we are your external personnel department. You give us the hiring decisions and the budget. We take it from there.

Here's what that actually looks like, month by month.

The Monthly Payroll Cycle

The Thai payroll month runs cleanly: salary calculations are finalised in the last week of the month, payslips and tax workings are sent to the client for approval, payments go out on the 25th–end-of-month, and the compliance filings hit the Revenue Department and Social Security Office in the first two weeks of the following month. Here are the five steps we run on every cycle:

Gross calculation. We pull each employee's base salary, monthly allowances (housing, transport, telephone, language premium, BOI-promoted-role bonuses), and any one-off items (sales commission, board fees, severance). Thai tax law treats allowances differently from base — some are taxable, some are partially exempt, some are exempt only if reimbursed against receipts. We make those distinctions per employee, per month.

Withholding calculation. Each employee's annualised projected income is run through the Thai progressive Personal Income Tax brackets (0% up to THB 150,000 annually, then stepping up to 35% above THB 5 million). The monthly withholding is 1/12 of the projected annual tax — adjusted on the fly when allowances or salaries change. For a senior expat earning THB 350,000/month, that's about THB 78,000/month withheld; we re-run the projection any month their income materially changes.

Social Security calculation. 5% employee + 5% employer on the contribution base, capped. The 2026 contribution base ceiling is THB 17,500 for most insured workers — meaning the max monthly contribution is THB 875 from each side. Anyone earning above THB 17,500 pays the cap; anyone below pays 5% of their actual salary. We file the SPS 1-10 monthly contribution form and remit to the Social Security Office.

Approval + payslip distribution. Before money moves, we send the client a one-page month summary (gross, net, tax, SSO, employer cost) plus the detailed worksheet. Once approved, we deposit net salary directly into each employee's bank account (or, if the client prefers, we issue cheques on behalf of the client). Each employee receives a confidential payslip — either by email with password protection or printed and sealed.

Filings. By the 15th of the following month, the PND.1 (monthly salary withholding tax return) and the Social Security monthly contribution form are e-filed with the Revenue Department and SSO. The corresponding tax and SSO payments are debited from the client's bank account or paid by us against a float. Receipts are scanned and stored in our client portal.

The Filings We Own End-to-End

One of the most common cleanup jobs we inherit is a Thai entity where the foreign HQ thought "payroll" meant "pay the salaries" and missed the Thai compliance layer. Here is the full list of what we file on behalf of every payroll-service client:

Form	What it is	Frequency	Deadline
PND.1	Monthly withholding tax return on salaries	Monthly	7th paper / 15th e-filing of following month
SPS 1-10	Social Security monthly contribution form	Monthly	15th of following month
PND.1 Kor	Annual salary withholding reconciliation	Annual	By end of February
50 Tawi	Annual tax certificate issued to each employee	Annual	By 15 February — employees need this for their personal PND.91 filing
Kor Tor 20 Kor	Employer's annual wage report to SSO	Annual	By end of February
SSO new-hire / leaver	Register or de-register an insured employee	Per event	Within 30 days of start / leave date

If you are running payroll yourself and any of those forms are unfamiliar, the Revenue Department's surcharge is 1.5% per month on overdue tax (capped at the unpaid amount), plus a fine that scales from THB 200 per late form upward. For BOI-promoted companies, the indirect cost is higher: a delinquent PND.1 history can block work-permit renewals for every foreign employee under the BOI scheme. That's the real risk — not the THB 200.

What Stays Confidential — and Why That Matters in Thailand

One specific reason foreign HQs outsource payroll to us, even when they have a Thai admin in-house: salary confidentiality. Thai office culture has a strong norm of comparing salaries openly between colleagues, and a leak from an in-house payroll officer can blow up team dynamics in a week. When our team holds payroll, the only people who ever see the per-employee numbers are: (a) the employee, (b) the HQ-side authorised contact, and (c) the two named partners on the engagement. Even the country manager doesn't see other employees' numbers unless they're explicitly authorised.

The practical version: we hand the country manager a department-level total, not a per-employee breakdown. Per-employee figures go only to HQ.

Two Delivery Models

Foreign HQs use one of two payment flows, depending on cash management preferences:

Model A — we pay the employees directly. HQ deposits the gross payroll + employer SSO + employer-side fees into our trust account by the 24th. We disburse to each employee's bank account on the 25th, file the PND.1 and SSO by the 15th of the next month, and the HQ sees one consolidated debit per month plus a monthly statement.

Model B — We prepare, the client pays. We prepare the per-employee net amounts and send the client an upload-ready file (or individual bank transfer instructions) by the 24th. Client treasury team executes the deposits. We still own all filings and remittances of the tax and SSO portions.

Model A is more common for foreign HQs with no Thai banking footprint. Model B is more common for companies that already have a Bangkok Bank or Kasikorn account and want the transfer to come from their own bank.

The 2026 Numbers You Should Know

If you're benchmarking what your Thai payroll should cost, here are the live 2026 figures every Thai employer is working off:

Item	2026 value
Personal Income Tax — top bracket	35% above THB 5,000,000 annual income
Personal Income Tax — first taxable bracket	5% from THB 150,001–300,000
Social Security ceiling (monthly contribution base)	THB 17,500
Social Security maximum contribution	THB 875/month each from employee + employer
Provident Fund (optional, employer-sponsored)	2–15% matched, tax-deductible for both sides
Standard severance (after 10 years of service)	300 days of latest wage
Annual leave minimum (Labour Protection Act §30)	6 days after 1 year of service
Maternity leave	98 days (45 days at full pay from employer, balance from SSO)

When Outsourced Payroll Makes Sense

Honest answer: it makes sense when your Thai headcount is small enough that a dedicated payroll officer is overkill, but big enough that one missed PND.1 actually hurts. In practice that's roughly 3–35 employees. Below 3, you can run it on a spreadsheet with quarterly review by an accountant. Above 35, you probably want an in-house HR/payroll lead, with us doing the compliance overlay.

The other reason it makes sense: when your HQ is in a timezone that doesn't overlap with Bangkok working hours, and the cost of a misfiled return is a 3-day email chain to fix what we could have resolved in 30 minutes locally.

What we charge. Our payroll service is priced per employee per month, with a base setup fee for new entities. Pricing depends on headcount, complexity (expats, BOI roles, provident fund, multiple branches), and delivery model. Reach out via the form on the homepage for a scoped quote.

The Backstop

The single best argument for handing this to our team: nothing changes when your in-house person leaves. The institutional knowledge, the Revenue Department contacts, the SSO district office relationships, the historical filings — all of it sits with our team. New country manager in your Thai entity? Their first payroll month runs exactly the same as the last one. That continuity is what we have spent three decades building.

Motherducker.tech is the modern delivery layer on top of our parent firm's compliance backbone. Same partners, same filings, same three decades of institutional knowledge — delivered through one point of contact.

Talk to us about Thai payroll: Use the intake form on the homepage, or email janice@motherducker.tech. We reply within one business day with a scoped quote.

Sources: Thailand Revenue Department Personal Income Tax structure 2026; Social Security Office Thailand contribution rates 2026; Labour Protection Act B.E. 2541 as amended; PwC Thailand Tax Summaries 2026. Current as of June 2026 — confirm with our consultancy before relying on these figures for commercial decisions.