How to Appeal an Indonesian Tax Court Decision to the Supreme Court (cassation), 2026

Tax cassation Indonesia is the extraordinary route by which a party to a tax dispute asks the Supreme Court (Mahkamah Agung) to correct an error of law made by the Tax Court, and in 2026 it remains a sharp, time-sensitive process shaped by ministerial (PMK) procedural refinements and the maturing of the e-Court filing environment. This guide is written for taxpayers, in-house counsel and external tax litigators who must decide, often under intense deadline pressure, whether to pursue cassation (kasasi) and, if so, how to file it correctly the first time. It sets out eligibility, the scope of the Supreme Court’s review, a step-by-step filing procedure, the required documents, deadlines, costs, and practical considerations relevant in 2026.

Every procedural claim below should be verified against the primary sources cited at the end before you act, because filing windows in cassation are short and unforgiving.

Last updated: September 2026. This article is general legal information, not advice on any specific matter. Confirm current Mahkamah Agung rules, the applicable PMK, and the e-Court fee schedule with local counsel before filing.

Overview, What is cassation (kasasi) in Indonesian tax litigation?

In tax litigation the position is distinctive. Under the Tax Court Law (UU No. 14 Tahun 2002 tentang Pengadilan Pajak), a decision of the Tax Court (Pengadilan Pajak) is itself a final decision, and the ordinary further remedy against it before the Supreme Court is Peninjauan Kembali (PK), not conventional cassation. Practitioners and commentators nonetheless often refer to the Supreme Court review stage using the general vocabulary of cassation, and the underlying principles of a Supreme Court review confined largely to questions of law apply.

Understanding that the review is not a full re-hearing is the single most important strategic fact in any tax cassation Indonesia matter, because it dictates what arguments will be heard and what will be dismissed as an impermissible re-argument of the facts. Confirm in each case, with counsel, whether the applicable route to the Supreme Court is PK under the Tax Court Law or another mechanism.

Definition and legal basis

In the Indonesian court hierarchy, the Tax Court issues decisions on tax disputes at first and, effectively, final instance for the merits. A party dissatisfied with a Tax Court decision may in defined circumstances seek Supreme Court review (Peninjauan Kembali). The procedural framework is governed by the Tax Court Law, by Supreme Court rules and regulations (PERMA), and is supplemented for administrative aspects by Ministry of Finance regulations (PMK). The consolidated statutory texts underpinning the tax framework, including the General Provisions and Tax Procedures Law (UU KUP, as most recently amended by the Harmonisation of Tax Regulations Law, UU No. 7 Tahun 2021), are published on the national legislation repository.

Because these instruments are periodically amended, always cite the latest consolidated version rather than relying on a superseded text.

When taxpayers consider Supreme Court review (practical triggers)

Supreme Court review is not an automatic next step. It is warranted when the Tax Court decision reflects a genuine error in the application or interpretation of law, or falls within the specific statutory grounds for PK, not merely an unfavourable weighing of evidence. Typical practical triggers include:

• Misapplication of a statutory provision. The Tax Court applied the wrong article of the UU KUP or a related PMK, or applied the correct provision incorrectly.
• Failure to apply mandatory law. A binding provision or procedural safeguard was ignored.
• Exceeding jurisdiction. The panel decided a matter outside its authority, or failed to decide part of the claim.
• Defective reasoning. The decision lacks adequate legal grounds or contains internally contradictory reasoning.
• Newly discovered decisive evidence. Under the specific PK grounds in the Tax Court Law, evidence that existed but could not be produced earlier and that would have changed the outcome.

Where the real grievance is that the Tax Court simply believed the tax authority’s witnesses or documents over yours, review is unlikely to help. That is a factual dispute, and the Supreme Court will generally decline to re-open it.

Eligibility, Who can seek Supreme Court review in a tax case?

Two questions determine eligibility: who has standing, and whether the decision is one that can be taken to the Supreme Court at all.

Standing (parties permitted)

The parties to the underlying Tax Court proceedings, the taxpayer and the Directorate General of Taxes (DJP), have standing to seek Supreme Court review. In practice, either side may pursue it: a taxpayer who lost, or the tax authority where the Tax Court ruled for the taxpayer. A party must act through an authorised representative holding a valid special power of attorney (surat kuasa khusus). Corporate taxpayers must ensure the signatory is duly authorised under the company’s constitutional documents and that identity and registration documents (NPWP, company deeds) are in order.

Which decisions are reviewable (finality and grounds)

Supreme Court review lies against a Tax Court decision on the merits, within the specific grounds and time limits set by the Tax Court Law. Interlocutory or purely administrative rulings are generally not independently reviewable. Because the Tax Court decision is itself final, the review before the Supreme Court is an extraordinary remedy rather than an ordinary appeal, and it is available only where the statutory grounds are met. Confirm in each case that the specific decision you wish to challenge is one the Supreme Court will entertain, filing outside the permitted grounds or window wastes the deadline and the fee.

Key legal limits, Scope of MA review: points of law vs facts

The scope of Supreme Court review is the defining constraint of any such application. Getting this right shapes the entire petition.

What the MA will (and will not) examine

The Supreme Court in reviewing a Tax Court decision principally examines whether the lower court:

• Applied the law correctly. Did it interpret and apply the governing statute and regulations properly?
• Stayed within its authority. Did it exceed or fall short of its jurisdiction?
• Observed mandatory procedure. Did it follow the procedural rules whose breach affects the validity of the decision?
• Overlooked decisive evidence. Within the defined PK grounds, whether newly discovered decisive evidence or a manifest error justifies review.

What the Court will not do is conduct a general re-hearing of the evidence. It does not routinely re-weigh witness credibility, re-assess documentary exhibits, or substitute its own factual findings for those of the Tax Court. Representative judgments in the Supreme Court decision database consistently reflect this division: pleas that dress up factual disagreement as legal error are rejected, while genuine errors in the application of law, or matters falling within the strict PK grounds, are addressed. Before drafting, review comparable tax rulings in that database to calibrate how the Court has framed the law/fact line in matters like yours.

Tactical implications for tax evidence and appeals strategy

The practical lesson is that the factual record must be built and protected at the Tax Court stage, because Supreme Court review will not repair evidentiary gaps. By the time a matter reaches this stage, the facts are effectively fixed. Your petition should therefore isolate, with precision, each legal error or applicable statutory ground and tie it to a specific provision or established principle, not narrate the dispute afresh. A tightly framed legal ground has far greater prospects than a broad complaint that the decision was “wrong.”

Step-by-step procedure to seek Supreme Court review (tax cassation Indonesia)

The procedural flow runs from obtaining the certified decision, through drafting and filing, to the Court’s deliberation and judgment. The numbered steps below map onto the timeline table and the required-documents table. Deadlines are short, treat Step 1 as urgent the moment the Tax Court decision is received.

1. Step 1, Confirm reviewability and obtain certified copies of the Tax Court decision. Verify that the decision is a final, reviewable ruling and that a statutory ground applies, then request a certified copy from the Tax Court registrar. The certified copy is the foundation of the petition and must bear the registrar’s certification. Request it immediately, as the review clock runs from the trigger event set by statute (for PK on newly discovered evidence, from discovery; otherwise from the point the decision is served or becomes known), so confirm the correct trigger in your case.

2. Step 2, Draft the petition and legal grounds. The petition sets out, formally, the grounds relied upon (alasan hukum). It should contain a concise chronology, a clear identification of the decision challenged, and, most importantly, a structured statement of each legal error or applicable statutory ground, each anchored to a specific provision or principle. The accompanying legal grounds memorandum (memori) develops the full legal argument with citations to statute and to relevant Supreme Court precedent. Budget five to ten business days for competent drafting, more for complex matters.

3. Step 3, Execute the power of attorney (surat kuasa khusus). Prepare and sign a special power of attorney authorising counsel to file and conduct the review. Where Supreme Court practice requires notarisation or particular formalities, comply. This can usually be completed the same day the petition is finalised.

4. Step 4, File through the Tax Court registry / Supreme Court channel (physical registry or e-Court). File the petition and its annexes either through the applicable Mahkamah Agung e-Court pathway, where available for the matter, or at the registry. Note that PK in tax matters is generally lodged via the Tax Court that issued the decision, which then forwards the file to the Supreme Court. e-filing requires prior registration and produces a confirmation receipt; retain the confirmation number and any login printout. Ensure every mandatory attachment is included, because incomplete filings risk administrative rejection.

   Filing must occur within the statutory window, so verify the exact number of days and the trigger under the Tax Court Law and any current PMK adjustment before you file.

5. Step 5, Pay court fees and provide any required security. Pay the filing fee through the prescribed channel (including e-Court payment where applicable) at filing or within the time the Court prescribes. Note that, under the tax collection framework, lodging a Supreme Court review does not automatically suspend tax collection; where any security or guarantee is relevant, follow the applicable rules and any court order. Keep the payment slip or e-Court proof as part of the filing bundle.

6. Step 6, Administrative screening, distribution to the panel, and any submissions. The registry screens the filing for completeness, then the case is distributed to a panel of Supreme Court justices. Distribution and scheduling take time and vary. The review is predominantly decided on the papers; where the Court permits or requests further submissions, respond precisely and within time.

7. Step 7, Judgment, publication, and next steps. The panel deliberates and issues its decision. The Tax Court Law sets a target period for deciding PK, though in practice complex matters take longer. The decision is subsequently published in the Supreme Court decision database. Address enforcement or administrative follow-up with the tax authority once the decision is issued.

Required documents, checklist and how to prepare them

Assemble the full bundle before filing. A missing or defective document is the most common cause of avoidable delay or rejection in tax cassation Indonesia matters.

For tax cases specifically, include the DJP-related documents relied upon in the litigation, audit reports and tax assessments (SKP), and ensure every quoted statutory provision refers to the latest consolidated text.

Authentication, translations and copies, local practice notes

Certified copies must come from the court registrar; do not substitute your own copies. Where any document is in a foreign language, provide a certified Bahasa Indonesia translation. Confirm current notarisation and attestation expectations for the power of attorney with the registry, as practice can vary. Keep an indexed master set of originals and file complete, legible copies, poor-quality attachments invite administrative queries that consume scarce time.

Timeline and deadlines, filing windows and typical durations

The review window is short. Calculate it from the correct statutory trigger and diarise it immediately. Under the Tax Court Law, a PK petition generally must be lodged within a defined period (measured in months) from the applicable trigger, for newly discovered evidence, from its discovery under oath; for other grounds, from when the decision is served or becomes final. Confirm the exact period and trigger in the operative statute for your ground. The table below sets out each step, who is responsible, and realistic durations.

Impact of recent PMK changes on timing

Ministry of Finance regulations refine aspects of tax administration and post-Tax Court procedure from time to time, with practical effect on documentary expectations and electronic processes. Because the precise numerical deadline and any transitional arrangements turn on the operative statute and regulation text, obtain and read the current instruments from the Ministry of Finance and national legislation repositories before calculating your window. Do not rely on a remembered figure: confirm the exact period and the trigger event against the current instrument, then build a calendar backwards from the filing deadline to your certified-copy request.

Costs and fees, court fees, professional fees and security

Cost planning in tax cassation Indonesia matters spans official fees, security where relevant, and professional fees. The items below are indicative only; verify official amounts against the current Supreme Court / e-Court fee schedule and treat professional fees as case-specific. Do not rely on any specific figure without confirming it against the current schedule.

Payment discipline and sanctions

Fees must be paid within the prescribed time; late or non-payment can lead to the filing not being processed, effectively forfeiting the review. Where any security is relevant to tax collection, follow the applicable statutory terms and any court order precisely. Confirm any refund or waiver arrangements against the current fee schedule rather than assuming they exist.

What is relevant in 2026, PMK and practice updates

Recent changes matter to anyone weighing tax cassation Indonesia, because they touch the mechanics that most often trip up filers: timing, documentation and the electronic pathway.

Key themes affecting Supreme Court review

The practical themes emerging from recent ministerial and court developments, as reflected in official materials, concern:

• Timing discipline. The need to calculate statutory review periods precisely from the correct trigger event.
• Documentary expectations. Clear expectations on the evidentiary and documentary record accompanying filings.
• Electronic processes. Continued alignment with electronic filing and administration, affecting registration, receipts and fee payment.

Because the operative detail lives in the statute and regulation text itself, treat the above as signposts and read the specific instruments before filing.

Practical steps to comply

Confirm the current filing window and trigger under the Tax Court Law and applicable rules; prepare the full documentary bundle to the standard the registry now expects; register for any e-Court pathway early so that a technical hurdle does not consume the deadline; and retain every electronic receipt and confirmation.

Common pitfalls and tactical tips

Most failed applications fail for avoidable reasons. Guard against the following:

• Missing the filing window. The deadline runs from the statutory trigger. Diarise it the day the decision arrives and request the certified copy immediately.
• Arguing facts instead of law. Re-litigating the evidence invites dismissal. Frame each ground as a discrete legal error tied to a statutory provision or established principle, or bring it squarely within a defined PK ground.
• Vague legal grounds. “The decision was wrong” is not a ground. Specify what law was misapplied, how, and why it altered the outcome.
• Incomplete bundle. A missing certified copy, unsigned power of attorney or absent payment proof triggers administrative rejection.
• Defective power of attorney. Ensure the signatory is properly authorised and that any notarisation requirement is met.
• Ignoring precedent. Anchor arguments in comparable Supreme Court decisions to show the Court its own consistent reasoning.

Objection, Banding and PK, comparison and when to choose each

Choosing the right remedy depends on the stage of the dispute and what you are challenging, the assessment, facts and law together, or a fundamental defect discovered later.

In short: use an objection to contest the assessment before the DJP; use banding at the Tax Court to re-litigate facts and law; and reserve PK before the Supreme Court for the exceptional case that meets its strict statutory grounds.

Templates and resources

Practitioners will benefit from a petition checklist, a special power of attorney (surat kuasa khusus) template, and a sample cover letter for filing. Where GLE publishes these as downloadable resources, keep filenames accessible and include a short instructions file. Related practitioner guides in this series include How to Prepare an Appeal (Banding) to the Tax Court in Indonesia, How to File an Objection (Keberatan) Against a Tax Assessment, and the Evidence & Witness Checklist for Indonesian Tax Litigation.

Next steps and conclusion

Tax cassation Indonesia rewards preparation and punishes delay: the window is short, the review is confined to law and to defined statutory grounds, and the documentary bundle must be complete and correctly certified before you file. Build and protect the factual record at the Tax Court stage, then frame each ground as a precise legal error or a matter within the PK grounds, tied to statute and precedent. Confirm the operative deadline, trigger and documentary requirements under the current Tax Court Law and applicable rules, register for any e-Court pathway early, and keep every receipt. Given how unforgiving the timeline is, the safest course is to obtain specialist tax litigation advice as soon as the Tax Court decision is received, well before the filing window closes.

Sources

1. Mahkamah Agung (Supreme Court), main site
2. Putusan Mahkamah Agung (Decision database)
3. e-Court Mahkamah Agung (e-filing portal)
4. Direktorat Jenderal Pajak (DJP), official site
5. Kementerian Keuangan (Ministry of Finance)
6. Peraturan.go.id (National legislation repository)