The 2026 ICC Rules: What Changes for Practitioners

The ICC's revised Arbitration Rules are due to take effect on 1 June 2026, applying to all requests filed from that date onward. The ICC's own summary emphasises efficiency, clarity and usability, but some of the changes have more significant practical consequences than that framing suggests.

Having spoken with arbitration practitioners across London, New York, Paris and the Gulf over the past few months, here is our read on which changes will have the most tangible impact on how ICC cases are run.

The End of Mandatory Terms of Reference

For decades, Terms of Reference were a defining feature of ICC arbitration: the document that recorded the parties' positions, identified the issues and framed the early conduct of the proceedings. Under the 2026 Rules, they are no longer mandatory. Tribunals retain the discretion to prepare them where they see value, but the expectation is that most proceedings will proceed without them. The ICC has pointed to its own data here: under the Expedited Procedure, where Terms of Reference were already optional, fewer than 25 out of more than 1,000 EPP cases involved them.

In practice, many arbitrators had already treated Terms of Reference as a procedural formality rather than a substantive exercise. The real shift here is that the Case Management Conference — which must be held within 30 days of the tribunal receiving the file — now becomes the central organising moment of the proceedings. The procedural timetable gets set at or shortly after the CMC, and it drives everything that follows, including the deadline for the final award.

For counsel, this means CMC preparation is more important than ever. If you want to shape the procedural calendar, propose bifurcation, or flag document production issues, the CMC is where that happens. It is no longer a preliminary step before the Terms of Reference — it is the main event.

A Hard Cut-Off for New Claims

Article 25 introduces a significant constraint: no new claims, which is likely to include counterclaims, after the first CMC without the tribunal's authorisation. Parties can still amend their case, but adding entirely new causes of action late in the day now requires permission — and tribunals will weigh disruption, delay, and the procedural timetable when deciding.

This has obvious implications for respondents considering counterclaims. If you are advising a respondent and think there may be additional claims worth pursuing, they need to be identified and filed before that first CMC. Waiting to see how things develop is no longer a cost-free strategy.

Award Timelines Get More Realistic

The old regime tied the final award deadline to the Terms of Reference — six months from the last signature, in theory, though in practice the Court routinely extended it. The 2026 Rules replace that fiction with something more honest: the President of the ICC Court now sets the time limit, aligned to the procedural timetable or based on a reasoned request from the tribunal.

For parties, this should mean greater predictability. The deadline will reflect the actual complexity and procedural calendar of the case rather than an aspirational default that everyone knew would be extended. For arbitrators, it introduces a degree of external accountability. The President's oversight adds a layer of institutional pressure to keep proceedings moving.

Expedited Procedure Expands

The threshold for automatic application of the Expedited Procedure rises to US$4 million (for agreements concluded on or after 1 June 2026). Given that over 40% of ICC cases in 2025 fell below that figure, a significant share of new filings will now proceed under expedited rules by default, with a sole arbitrator, a six-month award deadline, and streamlined submissions.

Parties with arbitration agreements drafted before June 2026 will not be caught by the new threshold, so there is no retrospective surprise. But for anyone negotiating new contracts, the opt-out question becomes relevant at a higher value than before.

Emergency Arbitration and Preliminary Orders

The 2026 Rules introduce preliminary orders within emergency arbitrator proceedings. Critically, these can be made ex parte where notifying the other side could frustrate the relief sought, such as where there is a risk of asset dissipation, destruction of evidence, or any scenario where speed and surprise are essential to preserving the status quo.

Due process safeguards remain: the emergency arbitrator must give all parties the opportunity to be heard immediately after issuing a preliminary order and can modify or revoke it based on further submissions. But the express acknowledgment of ex parte relief in ICC proceedings is a significant development for parties facing urgent threats.

The Broader Picture

Taken together, the 2026 revisions push ICC arbitration toward a more front-loaded procedural model. The early stages carry more weight than before — the CMC shapes the timetable, new claims face a hard cut-off, and disclosure obligations kick in immediately. Practitioners who approach the opening weeks of an ICC case with the same intensity they bring to the later stages will be better positioned under the new framework.

For teams managing complex ICC proceedings, the challenge is coordinating all of this preparation efficiently across large document sets and multiple workstreams. If you'd like to see how Crimson helps arbitration teams stay on top of their case files from day one, request a demo.