(a) Prerequisites to a class action. One or more members of a class may sue or be sued as representative parties on behalf of all only if (1) the class is so numerous that joinder of all members is impracticable, (2) there are questions of law or fact common to the class, (3) the claims or defenses of the representative parties are typical of the claims or defenses of the class, and (4) the representative parties will fairly and adequately protect the interests of the class.
Rule 23.Class actions
Group 4: Parties · Last amended September 1, 2017 · Last verified July 13, 2026
In one sentenceRule 23 sets the four-part test for certifying a class action, describes the three kinds of classes a court can certify, governs notice and settlement, and requires that at least half of any unclaimed residual funds from a class settlement go to the Legal Foundation of Washington to support civil legal aid.
Full Text of Rule 23
(b) Class actions maintainable. An action may be maintained as a class action if the prerequisites of section (a) are satisfied, and in addition:
(1) The prosecution of separate actions by or against individual members of the class would create a risk of
(A) inconsistent or varying adjudications with respect to individual members of the class which would establish incompatible standards of conduct for the party opposing the class, or
(B) adjudications with respect to individual members of the class which would as a practical matter be dispositive of the interests of the other members not parties to the adjudications or substantially impair or impede their ability to protect their interest; or
(2) The party opposing the class has acted or refused to act on grounds generally applicable to the class, thereby making appropriate final injunctive relief or corresponding declaratory relief with respect to the class as a whole; or
(3) The court finds that the questions of law or fact common to the members of the class predominate over any questions affecting only individual members, and that a class action is superior to other available methods for the fair and efficient adjudication of the controversy. The matters pertinent to the findings include: (A) the interest of members of the class in individually controlling the prosecution or defense of separate actions; (B) the extent and nature of any litigation concerning the controversy already commenced by or against members of the class; (C) the desirability or undesirability of concentrating the litigation of the claims in the particular forum; (D) the difficulties likely to be encountered in the management of a class action.
(c) Determination by order whether class action to be maintained; notice; judgment; actions conducted partially as class actions.
(1) As soon as practicable after the commencement of an action brought as a class action, the court shall determine by order whether it is to be so maintained. An order under this subsection may be conditional, and may be altered or amended before the decision on the merits.
(2) In any class action maintained under subsection (b)(3), the court shall direct to the members of the class the best notice practicable under the circumstances, including individual notice to all members who can be identified through reasonable effort. The notice shall advise each member that (A) the court will exclude the member from the class if the member so requests by a specified date; (B) the judgment, whether favorable or not, will include all members who do not request exclusion; and (C) any member who does not request exclusion may, if the member desires, enter an appearance through counsel.
(3) The judgment in an action maintained as a class action under subsection (b)(1) or (b)(2), whether or not favorable to the class, shall include and describe those whom the court finds to be members of the class. The judgment in an action maintained as a class action under subsection (b)(3), whether or not favorable to the class, shall include and specify or describe those to whom the notice provided in subsection (c)(2) was directed, and who have not requested exclusion, and whom the court finds to be members of the class.
(4) When appropriate, (A) an action may be brought or maintained as a class action with respect to particular issues, or (B) a class may be divided into subclasses and each subclass treated as a class, and the provisions of this rule shall then be construed and applied accordingly.
(d) Orders in conduct of actions. In the conduct of actions to which this rule applies, the court may make appropriate orders: (1) determining the course of proceedings or prescribing measures to prevent undue repetition or complication in the presentation of evidence or argument; (2) requiring, for the protection of the members of the class or otherwise for the fair conduct of the action, that notice be given in such manner as the court may direct to some or all of the members of any step in the action, or of the proposed extent of the judgment, or of the opportunity of members to signify whether they consider the representation fair and adequate, to intervene and present claims or defenses, or otherwise to come into the action; (3) imposing conditions on the representative parties or on intervenors; (4) requiring that the pleadings be amended to eliminate therefrom allegations as to representation of absent persons, and that the action proceed accordingly; (5) dealing with similar procedural matters. The orders may be combined with an order under rule 16, and may be altered or amended as may be desirable from time to time.
(e) Dismissal or compromise. A class action shall not be dismissed or compromised without the approval of the court, and notice of the proposed dismissal or compromise shall be given to all members of the class in such manner as the court directs.
(f) Disposition of Residual Funds.
(1) “Residual Funds” are funds that remain after the payment of all approved class member claims, expenses, litigation costs, attorneys’ fees, and other court-approved disbursements to implement the relief granted. Nothing in this rule is intended to limit the parties to a class action from suggesting, or the trial court from approving, a settlement that does not create residual funds.
(2) Any order entering a judgment or approving a proposed compromise of a class action certified under this rule that establishes a process for identifying and compensating members of the class shall provide for the disbursement of residual funds. In matters where the claims process has been exhausted and residual funds remain, not less than fifty percent (50%) of the residual funds shall be disbursed to the Legal Foundation of Washington to support activities and programs that promote access to the civil justice system for low income residents of Washington State. The court may disburse the balance of any residual funds beyond the minimum percentage to the Legal Foundation of Washington or to any other entity for purposes that have a direct or indirect relationship to the objectives of the underlying litigation or otherwise promote the substantive or procedural interests of members of the certified class.
Amendment History
Prior: RPPP Rule 23. Adopted May 5, 1967, effective July 1, 1967; amended December 1, 2005, effective January 3, 2006; amended, effective April 28, 2015; amended June 1, 2017, effective September 1, 2017.
Plain-English Summary
A class action lets a small number of named plaintiffs stand in for a much larger group of people with similar claims. Rule 23 doesn't let that happen automatically — it requires the class to clear four hurdles first. The class has to be so large that joining everyone individually would be impracticable. There has to be at least one question of law or fact common to the whole class. The claims or defenses of the representative plaintiffs have to be typical of the class as a whole, not some outlier situation. And the representatives, along with their lawyers, have to be capable of adequately protecting everyone else's interests.
Clearing those four hurdles isn't enough by itself — the case also has to fit one of three categories. The first covers situations where separate lawsuits would risk inconsistent rulings that leave the defendant with conflicting obligations, or where a ruling in one person's case would effectively decide the outcome for everyone else in the class. The second covers cases seeking injunctive or declaratory relief, where the party opposing the class has acted or refused to act on grounds that apply across the whole class. The third — the type most people picture when they hear 'class action' — requires that common questions predominate over individual ones, and that a class action is the best available way to resolve the dispute, taking into account how much individual class members want control over their own case, how much related litigation already exists, whether concentrating everything in one court makes sense, and how hard the class action would be to manage.
For that third category, Rule 23 requires the best notice practicable to the class, including individual notice to anyone who can be identified without unreasonable effort. The notice has to tell class members they can opt out by a set date, that the judgment binds everyone who doesn't opt out, and that they can appear through their own lawyer if they want. Certification orders can be conditional and revised before the case is decided, cases can be split by issue or into subclasses, and a certified class action can't be dismissed or settled without court approval and notice to the class.
Rule 23(f) addresses a problem specific to consumer and similar class settlements: money set aside for the class that nobody claims. Once the claims process runs its course and money is still left over, at least fifty percent of those residual funds must go to the Legal Foundation of Washington, which funds programs that give low-income Washington residents access to the civil justice system. A court can send the remaining share to the Legal Foundation as well, or to another organization whose work connects to the underlying case — but nothing in the rule forces a settlement to create residual funds in the first place; parties can structure a settlement so there's nothing left over to distribute.
Frequently Asked Questions
What are the four requirements a class must meet under Rule 23(a)?
Numerosity (the class is too large for individual joinder to be practical), commonality (a shared question of law or fact), typicality (the representatives' claims or defenses match the class as a whole), and adequacy (the representatives will adequately protect the class's interests).
What are the three types of class actions under Rule 23(b)?
One where separate suits risk inconsistent rulings or would effectively decide the case for absent members; one seeking injunctive or declaratory relief against conduct that applies to the whole class; and one where common questions predominate over individual ones and a class action is the superior way to resolve the dispute.
Do class members have to be individually notified?
In a class certified under the predominance-and-superiority category, yes — the court must direct the best notice practicable, including individual notice to anyone who can be identified through reasonable effort, and that notice must explain the right to opt out.
Can a class action be settled without a judge's approval?
No. Rule 23(e) requires court approval before a class action can be dismissed or compromised, and notice of the proposed dismissal or settlement must go out to the class.
What happens to money from a class settlement that no class member claims?
Rule 23(f) calls that money 'residual funds.' Once the claims process is exhausted, at least fifty percent of any residual funds must be disbursed to the Legal Foundation of Washington, which supports access to the civil justice system for low-income residents. The court decides where the rest goes, which can also be the Legal Foundation or another entity connected to the case.
Does every class settlement have to leave residual funds?
No. Rule 23(f)(1) makes clear that nothing in the rule stops parties from structuring a settlement that doesn't create residual funds at all.
Can a class action be limited to certain issues instead of the whole case?
Yes. Rule 23(c)(4) allows a class action to be maintained on particular issues, or lets the court divide the class into subclasses that are each treated as their own class.
Source & verification. Rule text and amendment history are
reproduced verbatim from the Washington Superior Court Civil Rules, adopted by the
Supreme Court of Washington. Last verified July 13, 2026. ·
Official source
Also known as: class action rule washingtonclass certification requirementsresidual funds class actionlegal foundation of washington cy presnumerosity commonality typicality adequacyopt out class notice