Service Agreement in Thailand: Hire of Work vs Employment Contract, What Actually Changes

Most of what people in Thailand casually call a "service agreement" is what the law classifies as a contract for hire of work (สัญญาจ้างทำของ), not an employment contract (สัญญาจ้างแรงงาน). The distinction is not just vocabulary: it has real consequences for VAT, stamp duty, social security, and even who owns the work that gets delivered.

Many SMEs sign contracts with outside contractors without realizing that, in practice, they are building an employment relationship, even though the document says "service agreement" at the top. The fallout can arrive later as a retroactive tax assessment or a dispute over employee rights. This article explains the difference clearly, the clauses a B2B service agreement needs, and how to go from negotiating over chat to a properly signed document.

TL;DR: A contract for hire of work is one where the contractor commits to delivering a finished result and keeps the freedom to decide how the work gets done. An employment contract, by contrast, is built on an employer-employee relationship with direct supervision and control. That difference drives VAT, stamp duty, social security, and legal ownership of the work product. A solid B2B service agreement should cover at least 6 areas, from scope of work to jurisdiction, and it can be signed electronically under the Electronic Transactions Act B.E. 2544 (2001).

What you'll learn in this article

• How a contract for hire of work differs from an employment contract, and why the document's title is not what decides
• The 4 tax and legal consequences that change depending on which contract type you choose
• Who owns the work product by legal default if the contract says nothing
• The 6 clauses every B2B service agreement needs to prevent disputes
• How to turn a LINE or email agreement into a properly signed document in minutes

What is a contract for hire of work, and how does it differ from an employment contract?

A contract for hire of work is one where the contractor agrees to complete an agreed piece of work, and the hirer agrees to pay once the work is done. The clearest difference from an employment contract is that the contractor is free to choose their own working methods. They are not under the hirer's direct command the way an employee is under an employer.

A point that often gets overlooked: the contractor under a hire-of-work contract can be a juristic person; it does not have to be an individual. An employment contract is different: the employee must always be a natural person. This is why a business can perfectly well engage a company or agency as its service provider under a hire-of-work arrangement.

The single most important thing to understand is that the title on the document does not decide anything. Writing "Service Agreement" or "Contract for Hire of Work" at the top does not guarantee that the relationship works that way in practice. If, in reality, the hirer closely controls the contractor's working hours, workplace, and methods the way an employer controls an employee, the relationship may be treated as employment in practice, whatever the paperwork says.

Why misclassifying the contract has real tax and legal consequences

Getting the classification wrong is not a legal technicality. It changes the taxes and obligations the business actually has to carry. Here are the main differences to know before choosing a contract type.

What SMEs often do not see coming is this: if the contract is misclassified from the start, for example labelled hire of work while functioning as employment in practice, the result can be a retroactive tax assessment or an employee-rights claim later on. Both cost far more than anyone expects at the beginning.

Who owns the work: copyright in service agreements

If the contract says nothing about copyright, the legal default in a hire-of-work arrangement is that copyright in the work belongs to the hirer. That is the opposite of an employment contract, where copyright generally stays with the creator (the employee) unless agreed otherwise.

This is exactly where advertising agencies and software companies that subcontract tend to slip without noticing. If an agency hires a freelancer to produce work for a client without a clear copyright clause, it may be uncertain whether the agency can hand that work to the client with full rights to use it. The safest path is to always spell out ownership of the work in the contract instead of leaving it to legal defaults.

The 6 clauses every B2B service agreement needs

A well-drafted business-to-business (B2B) service agreement should cover at least these 6 areas, whether you are engaging a marketing agency, an IT contractor, or an ongoing maintenance provider.

1. Scope of work: what the work covers in detail, and what falls outside it
2. Deliverables and deadlines: delivery dates for each milestone, plus the acceptance standard
3. Fees and payment terms: the amount, the payment method, and the due dates
4. Termination and compensation: the conditions under which either party can end the contract, and what happens to fees for work already done
5. Confidentiality: what each party's information must stay confidential, during and after the contract
6. Governing law and jurisdiction: stating that Thai law applies and which court decides if a dispute arises

In practice, many businesses agree on the deal over email or LINE first, then write the contract in a rush afterwards. Clause 4 (termination) and clause 5 (confidentiality) are the ones that usually get dropped in that rush, even though they are the two clauses most likely to become the center of a dispute when the business relationship sours.

Fees, payment, and stamp duty: where businesses slip up

A contract for hire of work generally carries a stamp duty obligation, unlike an employment contract, which does not. This is the point SMEs often only discover at audit time or when filing taxes.

The safe practice is to consult your accounting firm or tax advisor before finalizing the contract value and payment structure, especially for high-value contracts or long-running engagements. A stamp duty liability calculated wrong can turn into an unexpected expense later.

From LINE or email threads to a signed service agreement in 5 minutes

Moving from a negotiation over LINE or email to a properly signed contract is faster than most people think. The basic steps: upload the contract template, fill in the parties' names, send a signing link with OTP identity verification, and wait for the completed document.

One thing worth getting right: OTP verification strengthens the evidentiary weight of the document; it is not a legal precondition for the document to be valid. A document signed with an ordinary electronic signature is already binding under the Electronic Transactions Act B.E. 2544 (2001). What OTP and the signing audit trail add is a clearer way to prove who signed, should a dispute arise, as explained in how e-signed documents work as court evidence.

If the other party is a solo freelancer rather than a company, see the freelance contract guide, which covers a specific case that differs from the B2B service agreement discussed here. If you need broader protection for confidential information, see the NDA template guide separately. And if the relationship really amounts to regular employment, use an employment contract instead. For businesses that issue a quotation before signing, see the quotation template guide as well.

Frequently asked questions

Does a contract for hire of work require stamp duty?

Generally yes. A contract for hire of work carries a stamp duty obligation, unlike an employment contract. Consult your accounting firm or tax advisor to calculate the correct amount based on the value of each contract.

Can the contractor be a company, or does it have to be an individual?

The contractor under a hire-of-work contract can be a juristic person; it does not have to be an individual. This is a key structural difference from an employment contract, where the employee must always be a natural person.

Can a service agreement be signed online? Is it legally valid?

Yes. A service agreement can be signed with an electronic signature under the Electronic Transactions Act B.E. 2544 (2001), which makes it legally binding without printing the document and signing by hand.

What happens if the contract is misclassified (labelled hire of work but really employment)?

The consequences depend on the facts of each case, such as the degree of supervision and how independently the work was actually done. It may lead to a retroactive tax assessment or a dispute over employee rights. This content is general information, not legal advice for any specific case. Consult a legal advisor about your situation.

The bottom line

The contract type you choose is not a paperwork detail. It determines the taxes, social security obligations, and ownership of the work your business is responsible for. A contract for hire of work and an employment contract look alike, but their legal consequences genuinely differ. A service agreement that covers all 6 areas, from scope of work to jurisdiction, meaningfully reduces your risk when a dispute arises.

If you are about to issue a service agreement to a partner or contractor, try a complete service agreement template and send it for electronic signature instead of negotiating in chat. Try Jabmue to see the service agreement templates in the gallery, or see current pricing.

This content is general information, not legal or tax advice for any specific case. Consult a legal advisor or accountant before making decisions on high-risk matters.