Arbitration at the Thai Arbitration Institute (TAI) 2026: Statement of Claim Requirements, Documents, Fees and Timeline for Foreign Parties

Key takeaways

• Two preconditions for filing at TAI: the contract contains an arbitration agreement or clause, and the parties have agreed that TAI administers the proceedings.
• The statement of claim (form Aor Tor 7) must contain eight items; a missing item can mean the file is sent back for correction before the case proceeds.
• Six documents are required; the company affidavit must be an original issued within the last three months, not a copy.
• The expense deposit is THB 15,000 per party for Thai-language proceedings and THB 30,000 per party for proceedings in English or another foreign language, paid with the claim; a foreign party's case is usually in the second category.
• Copies must suffice for the respondents and the tribunal, in practice "number of respondents plus number of arbitrators", and every copy must be certified as a true copy.
• An editable electronic file (for example .docx) must be lodged; a scanned PDF does not qualify.
• The timeline is 15/30/180/30 days: 15 days for the defence, 30 days after the tribunal is constituted to set the schedule, a hearing schedule of no more than 180 days (extendable by TAI), and the award within 30 days of closing.
• Language: under the Fifth Amendment, in force since 1 September 2023, a claim in neither Thai nor English, or filed where the clause is silent on language, needs a Thai translation. Fix the language in the clause.
• TAI charges no institutional fee. It is funded from the judiciary's budget, which is a material difference from private institutions.

For a foreign company doing business in Thailand, arbitration matters more than most people assume.

The reason is that Thailand does not enforce foreign court judgments. A judgment from a court in New York, London or Singapore has no direct effect against assets in Thailand; the creditor has to sue again in a Thai court. A foreign arbitral award that meets the New York Convention's requirements, by contrast, can be enforced. That makes arbitration the only dispute-resolution route that actually crosses the border, which is why the choice of seat and institution is covered at length in our guide to debt recovery in Thailand .

Among the institutions in Thailand, the Thai Arbitration Institute (TAI) is the principal one. Established in 1989 and hearing cases since 1990, it sits within the Office of the Judiciary, the administrative arm of the Thai courts. Its 2025 annual report records 3,013 cases from 1990 to 2025, with about THB 1.08 trillion in dispute.

This guide sets out, under TAI's current rules and practice, how to prepare a filing: when you can refer a dispute, what the statement of claim must say, which documents to bring, and what happens after filing. It closes with the three points that matter most to a foreign party: language, the expedited procedure, and cost.

1. When you can refer a dispute to TAI

Two conditions must both be met:

• The contract contains an arbitration agreement or arbitration clause providing that disputes are to be resolved by arbitration.
• The parties have agreed that TAI administers the proceedings.

Neither alone is enough. A clause that merely says "disputes shall be referred to arbitration" without naming an institution invites argument; a clause naming another institution, such as THAC, takes the case outside the TAI Rules.

TAI or THAC?

Foreign counsel often know only the Thailand Arbitration Center (THAC), which is a private institution established under its own Act in 2007 and markets itself internationally. TAI is the older body, part of the court administration, and charges no institutional fee. Both administer arbitrations in English, both produce awards enforceable in Thailand and abroad under the New York Convention, and both are commonly named in Thai commercial contracts. The practical differences are cost (TAI's expense deposits and arbitrator fees run lower for the same claim), the pool of arbitrators each maintains, and procedural style; TAI's procedure is more court-like. The choice is made at signing, and it should be made deliberately rather than by default.

The two forms

Where the preconditions are met, the claimant files with TAI:

The applicable rules are the TAI Arbitration Rules B.E. 2560 (2017) as amended, most recently by the Fifth Amendment published in the Government Gazette on 19 September 2023 and in force from 1 September 2023.

2. The eight items in the statement of claim (Aor Tor 7)

Under Article 7 of the TAI Rules the claim must state seven items; TAI's filing guidance adds the signature of the claimant or its authorised representative, making eight. They fall into three groups: the basis of jurisdiction, the substance of the dispute, and formalities.

Jurisdiction (items 1 to 3)

Item 1: a request that the dispute be resolved by arbitration. State in the opening paragraph that the claimant requests arbitration of the dispute under the TAI Rules.

Item 2: names, addresses and email addresses (if any) of both parties. Names must match the company affidavit or identity document exactly; the address must be one at which service can actually be made; give an email address to facilitate service. Mismatched names are among the commonest reasons a file is returned.

Item 3: the arbitration clause or agreement. Cite the clause number, quote it in full and attach a copy of the contract. A bare reference to "the arbitration clause in the contract" without the text is likely to be sent back.

Substance (items 4 to 6)

Item 4: the contract or legal relationship giving rise to the dispute. Give the contract's title, date and parties, and attach the relevant documents: purchase orders, invoices, amendments.

Item 5: the facts relied on and the amount claimed. Set out the facts chronologically; break the amount into principal, interest and damages with the calculation.

Item 6: the relief sought. The relief must be specific and enforceable: the amount, the interest rate, the date from which interest runs, and who bears the costs. Vague relief causes trouble at the enforcement stage even after a win.

A reminder: the amount claimed drives the arbitration costs and the arbitrators' fees. Explain the fee structure to the client before filing.

Formalities (items 7 and 8)

Item 7: the number of arbitrators.

Item 8: signature.

A file missing any of the eight items may have to be corrected before the case proceeds.

3. The six documents

Identity documents depend on the type of party

The company item is where filings most often fail: original, and within three months, both conditions.

Foreign parties. The rules are written for Thai documents. A foreign company should expect to produce its certificate of incorporation or good standing and evidence of the signatory's authority, notarised and then legalised through a Thai embassy or consulate; Thailand has acceded to the Apostille Convention, but the Convention takes effect for Thailand only on 28 February 2027, so until then an apostille alone is not accepted. For an individual, a passport replaces the ID card and house registration. Confirm with TAI in advance what it will accept rather than discovering the gap on filing day.

Aor Tor 20 and Aor Tor 6 are different documents

They are often confused but do different jobs.

Power of attorney (Aor Tor 20) authorises a person to act for the party in the case. Note:

• Stamp duty must be affixed unless exempt: THB 10 for authority to do one act, THB 30 for authority to do more than one act, and THB 30 per attorney where several may act separately
• Attach copies of the identity documents of both the principal and the attorney
• A corporate principal must affix its company seal

Authorisation to file (Aor Tor 6) is used only when neither the party nor its attorney lodges the documents in person, for example when a law firm's clerk delivers the file.

In short: Aor Tor 20 answers "who represents the party in this case"; Aor Tor 6 answers "who is making this trip to the counter".

Nomination of arbitrator (Aor Tor 10)

Required only where there is more than one arbitrator. Before filing:

• Approach the proposed arbitrator and obtain their written consent first; do not file and chase the consent later
• Check the candidate's impartiality and independence and the absence of conflicts

4. Copies and the electronic file

How many copies

Article 7 requires copies sufficient for service on the respondents and the tribunal. In practice: number of respondents plus number of arbitrators. One respondent and three arbitrators means four sets, plus one for your own file.

Every copy certified

Every document served on the respondents and the tribunal must be signed and certified as a true copy of the original. A missed certification is a common reason for correction.

The editable file (CD-ROM)

An editable electronic version of the statement of claim (for example .docx) must be lodged on the day of filing. A scanned PDF is not an editable file and does not meet the requirement. This looks trivial and is discovered on filing day more often than anything else. The requirement comes from TAI's filing guidance; TAI also operates an E-Arbitration system, so confirm with TAI which method applies at the time of filing.

5. Pre-filing checklist

6. Six common mistakes

None of these is a point of law. Each is a procedural slip, and each is enough to delay the case.

7. The timeline after filing

The draft award goes to TAI for a review of form, and TAI then serves the award on the parties. On receipt it is final and binding.

Enforcing the award abroad, and foreign awards in Thailand

Thailand acceded to the New York Convention on 21 December 1959 without reservations. A TAI award can therefore be enforced in the United States, the United Kingdom, Singapore and the other 170-odd Convention states through the Convention's procedure, and an award made in a Convention state can be enforced in Thailand under sections 41 to 44 of the Arbitration Act B.E. 2545 (2002), at a court fee of 1% of the amount claimed capped at THB 100,000. The United States applies the Convention with the reciprocity and commercial reservations, both of which a TAI award in a commercial dispute satisfies. Note the contrast once more: a foreign court judgment gets none of this.

8. Three things that can happen during the proceedings

A challenge to jurisdiction

A party may argue that there is no valid arbitration agreement, that the dispute falls outside it, or that TAI should not administer it. TAI notifies the other party, invites its views and objections, and decides. If there is prima facie evidence of an arbitration agreement, the proceedings continue; if not, they end. This is why item 3 of the claim should quote the clause in full and attach the contract: adequate prima facie evidence lowers the risk of the case stalling.

Settlement

Where the parties settle during the proceedings, there are two routes: the claimant withdraws the claim; or the parties submit the settlement agreement, a tribunal is constituted, and the tribunal renders an award on agreed terms. The second route produces an enforceable award; a bare settlement contract does not, and if the counterparty's willingness or ability to perform is in doubt, the consent award is the safer course.

Interim measures

Under Article 39 of the TAI Rules the tribunal may, on application, order such interim measures of protection as it considers appropriate and may require security. But section 16 of the Arbitration Act B.E. 2545 provides only for the court to order interim measures, and there is no express provision on enforcing a tribunal's order. Where coercive force is needed, apply to the court under section 16; the TAI Rules confirm that applying to the tribunal does not prejudice the right to apply to the court.

9. Three points for foreign parties

9.1 Language: fix it in the clause, and file in English

Under the Fifth Amendment, if the arbitration agreement does not specify Thai or English as the language, or the claim is filed in a language other than Thai or English, the claimant must supply a Thai translation of the statement of claim; the same applies to the defence, the counterclaim and the reply. The translation is treated as a required item under Article 7, and TAI may order correction under Article 8 if it is missing.

For an English-speaking party the practical rules are: name English as the language of the arbitration in the clause itself, so that the translation duty never arises; file the claim in English; and budget for the foreign-language deposit of THB 30,000 per party and for the possibility, discussed below, that TAI sets the arbitrators' fee deposit at a multiple. Contracts with Thai counterparties are often signed in two languages; if the clause is silent on the language of the arbitration, the translation obligation, its cost and its delay land on the party that needs the award.

9.2 Expedited procedure: claims up to THB 5 million

The Fourth Amendment, in force from 1 October 2021, introduced an expedited procedure. TAI may allow it where the parties agree, or where the claim and counterclaim together do not exceed THB 5 million.

Three points: the request must be made before the tribunal is constituted; TAI has a discretion, so meeting the threshold does not make it automatic; and, unless the parties agree otherwise, it applies in principle only to contracts made after 1 October 2021. The expedited procedure normally uses a sole arbitrator, closes within 60 days of the tribunal's constitution, and produces the award within 15 days; the expense deposit is THB 3,000 per party.

For a commercial dispute of modest value this shortens the timetable and the cost considerably. Assess eligibility before filing.

9.3 TAI charges no institutional fee

TAI is funded from the judiciary's budget and charges no administrative fee. That is a material difference from private institutions in Thailand and abroad, and belongs in any comparison of institutions.

Arbitrators' fees are still calculated on a sliding scale by the amount in dispute, and other costs are charged at actual cost; for proceedings in a foreign language or complex cases, TAI may raise the deposit for arbitrators' fees to 1.5 to 5 times the standard amount. Explain the whole cost structure to the client before filing.

The TAI procedure itself is not complicated. Corrections and delays rarely come from points of law; they come from document details: an expired company affidavit, short stamp duty, an uncertified copy, a file in the wrong format. Each can be checked before filing, and the cost of checking is far below the cost of the delay.

Beneath that lies the more fundamental layer: whether you reach arbitration at all depends on how the clause was drafted. Does it name TAI? Does it fix the number of arbitrators? Does it fix the language? Each is a single sentence at signing and a potential obstacle once a dispute has started, which is why the arbitration clause deserves attention in every share purchase agreement and joint venture agreement with a Thai counterparty.

Frequently asked questions (FAQ)

When can a dispute be referred to TAI?

Two conditions must both be met: the contract contains an arbitration agreement or clause providing for arbitration, and the parties have agreed that TAI administers the proceedings. A clause that refers to arbitration without naming an institution invites argument, and a clause naming another institution takes the case outside the TAI Rules. Where the conditions are met, the claimant files a statement of claim (Aor Tor 7), and, where there is more than one arbitrator, a nomination and consent (Aor Tor 10). The applicable rules are the TAI Arbitration Rules B.E. 2560 (2017) as amended.

What must the statement of claim (Aor Tor 7) contain?

Eight items; seven come from Article 7 of the TAI Rules and the eighth, the signature, from TAI's filing guidance: (1) a request for arbitration; (2) the parties' names, addresses and email addresses; (3) the arbitration clause or agreement; (4) the contract or legal relationship giving rise to the dispute; (5) the facts relied on and the amount claimed; (6) the relief sought; (7) the number of arbitrators where the contract is silent; (8) the signature of the claimant or its authorised representative. A missing item may require correction before the case proceeds. The commonest errors are item 2 (names must match the company affidavit exactly) and item 3 (quote the clause in full and attach the contract). The amount claimed also drives the costs and arbitrators' fees.

Which documents are needed and what does it cost to file?

Six documents: the statement of claim with attachments; identity documents; a power of attorney (Aor Tor 20) with ID copies; an authorisation to file (Aor Tor 6) where the filing is not in person; a nomination and consent of arbitrator (Aor Tor 10) where there is more than one arbitrator; and the expense deposit of THB 15,000 per party for Thai-language proceedings or THB 30,000 per party for foreign-language proceedings, paid by the claimant on filing and by the respondent with the defence, topped up or refunded as the case requires. Identity documents depend on the type of party: a company produces an original affidavit issued within three months and the director's ID; a foreign company should have its corporate documents legalised and confirm with TAI what it accepts. TAI charges no institutional fee, but arbitrators' fees and other costs are calculated on the amount in dispute.

How many copies, and what are the e-file requirements?

Copies sufficient for the respondents and the tribunal: in practice, respondents plus arbitrators. One respondent and three arbitrators means four sets, plus one for your own file. Every document served on the respondents and the tribunal must be certified as a true copy; a missed certification is a common reason for correction. An editable electronic file of the claim (for example .docx) must be lodged on a CD-ROM on the day of filing; a scanned PDF does not qualify.

How long does a TAI arbitration take?

The main periods are 15/30/180/30 days: the respondent files its defence and counterclaim within 15 days of receiving the claim; the preliminary schedule is set within 30 days of the appointment of the last arbitrator; the hearing schedule is capped at 180 days, including hearings and evidence, though this is a cap on the schedule rather than a guaranteed completion date and TAI may extend it; and the award is made within 30 days of the close of proceedings. The draft goes to TAI for a review of form before service, and the award is final and binding on receipt. Where the claim and counterclaim together do not exceed THB 5 million, or the parties agree, the expedited procedure can be requested before the tribunal is constituted, at TAI's discretion.

Can we file the claim in English?

Yes, and for an English-speaking party that is the right course. Under the Fifth Amendment, a claim filed in a language other than Thai or English, or filed where the arbitration agreement is silent on the language, requires a Thai translation, and the same applies to the defence, counterclaim and reply. A claim in English under a clause that names English needs no translation. The foreign-language expense deposit is THB 30,000 per party, and TAI may set the arbitrators' fee deposit at 1.5 to 5 times the standard amount for foreign-language or complex cases. Fix the language in the clause at signing; it is far cheaper than dealing with translations after the dispute has started.

Can a TAI award be enforced in the United States, and a US award in Thailand?

Both, through the New York Convention. Thailand acceded on 21 December 1959 without reservations; the United States acceded in 1970 with the reciprocity and commercial reservations, which a TAI award in a commercial dispute satisfies. A US award is enforced in Thailand by application to the court under sections 41 to 44 of the Arbitration Act B.E. 2545, at a court fee of 1% of the amount claimed capped at THB 100,000. A foreign court judgment, by contrast, is not enforceable in Thailand at all; the creditor must sue afresh.

What happens if the respondent says there is no arbitration agreement?

That is a jurisdictional challenge. The respondent may argue that there is no valid agreement, that the dispute falls outside it, or that TAI should not administer it. TAI notifies the other party, invites its views, and decides. If there is prima facie evidence of an arbitration agreement, the proceedings continue; if not, they end. That is why item 3 of the claim should quote the clause in full and attach the contract.

We settled during the proceedings. What now?

Two routes. The claimant may withdraw the claim; or the parties may submit the settlement agreement, have a tribunal constituted, and obtain an award on agreed terms. The difference matters: a consent award is enforceable, so if the counterparty later fails to perform you can go straight to enforcement, whereas a bare settlement contract is not and would have to be sued on. If the counterparty's ability or willingness to perform is in doubt, take the second route. The tribunal may also order interim measures on application during the proceedings.

How Louis Group can help

Louis Group has offices in Taipei and Bangkok, with Thai-qualified lawyers working alongside Taiwanese colleagues in English. We advise foreign companies on arbitration and commercial disputes in Thailand: drafting and reviewing arbitration clauses before signing, preparing and filing the TAI statement of claim and documents, representation in the proceedings, applications for interim measures, settlement negotiation, and enforcement of awards in Thailand and abroad. If your contracts with Thai counterparties contain arbitration clauses, have their enforceability reviewed before a dispute arises.

Author: Sopon Sirimongkolrat , Founding Partner, Louis & Partners Thailand, Thai-qualified lawyer practising company law, commercial disputes and arbitration.

*This article is general legal information, not advice on a specific case. TAI's forms, fee schedules and procedural rules may change; before filing, take advice from a Thai-qualified lawyer and rely on the latest forms and fee schedules published by the Thai Arbitration Institute (tai.coj.go.th).*

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