a Effective date. These rules and any amendments take effect at the time specified by the Supreme Court.
Rule 81.Effective date; applicability.
Last verified July 1, 2026
In one sentenceRule 81 explains when a new rule or amendment takes effect and how it applies to actions that were already pending when the change occurred.
Full Text of Rule 81
b Applicability. Upon the effective date, a rule or amendment governs:
1 proceedings in an action commenced after its effective date; and
2 proceedings after that date in a pending action unless:
A the Supreme Court specifies otherwise in its order adopting the rule or amendment; or
B the court determines that applying the rule or amendment in a particular action would be infeasible or work an injustice, in which event the former rule or procedure applies.
Amendment History
Promulgated by R-16-0010, effective January 1, 2017.
Plain-English Summary
A new rule or amendment becomes effective on whatever date the Arizona Supreme Court specifies when adopting it. From that point on, the rule governs any action filed after the effective date, and it also governs further proceedings in cases that were already pending, applying going forward rather than reopening anything already done.
That default rule for pending cases has two exceptions. The Supreme Court can specify different treatment in the order that adopts the rule or amendment, and a court can decline to apply a new rule or amendment to a particular pending action if doing so would be infeasible or would work an injustice — in which case the older rule or procedure continues to apply in that case.
Frequently Asked Questions
When does a new rule amendment take effect?
On the date the Arizona Supreme Court specifies when it adopts the rule or amendment.
Does a new rule apply to my case if it was already pending when the rule changed?
Generally yes, to further proceedings in the case going forward, unless the Supreme Court says otherwise or the court finds that applying the new rule would be infeasible or unjust.
What happens if applying a new rule to a pending case would be unfair?
The court can decline to apply the new rule or amendment to that action, and the former rule or procedure continues to govern instead.
Source & verification. The rule text and History are reproduced verbatim from the
official Arizona Rules of Civil Procedure (Ariz. R. Civ. P. 81). Prescribed by the Supreme Court of Arizona (Ariz. Const. art. 6, § 5). The plain-English summary is original and written by us. Last verified July 1, 2026. ·
Official source
Also known as: effective date rule