How does a class action lawsuit work?

Most class actions begin with a lawyer hearing from affected people or spotting a pattern: a data breach notice, a recall, an FTC complaint, or a wave of consumer complaints about the same fee. Firms often announce that they are investigating before anything is filed. An investigation is not a lawsuit, and nobody has proven anything at that point.

The case formally starts when a complaint is filed in court. The complaint names one or more class representatives, describes the proposed class (for example, "all U.S. residents whose data was exposed in the March 2024 breach"), lays out the legal claims, and asks for money, a court order, or both. Often, several firms file similar complaints in different courts within weeks. Federal cases may be combined through multidistrict litigation, and the judge may appoint interim class counsel to lead the group.

Filing also affects deadlines. Under the Supreme Court's 1974 decision in American Pipe & Construction Co. v. Utah, the filing of a class action suspends the statute of limitations for all asserted members of the class. That protection has limits, and statute of limitations rules vary by claim and state.

The company's first move is usually a motion to dismiss, arguing that even if everything in the complaint is true, the law does not allow the claim. Many consumer cases are narrowed or ended here. Another common defense is a motion to compel arbitration: if the terms of service contained an arbitration clause with a class action waiver, the company may ask the court to send each customer's claim to private, individual arbitration instead of a class case.

These early rulings can take a year or more. If the case survives, it moves into discovery. If it does not, the plaintiffs may amend the complaint or appeal. Our guide on what happens if a class action loses explains what that means for class members, who generally keep their individual rights if no class was ever certified.

Discovery is the evidence phase. The sides exchange documents, take depositions, and hire experts. In consumer cases, the key evidence is often internal company data: how many people paid a fee, how a product was marketed, or what security controls were in place before a breach.

Then comes the pivotal ruling. Under Federal Rule of Civil Procedure 23, the judge must decide "at an early practicable time" whether to certify the class. The plaintiffs must prove numerosity, commonality, typicality, and adequacy, plus one of the Rule 23(b) categories. See what class certification means for the details.

Under Rule 23(f), a party can petition the court of appeals for permission to appeal a certification ruling within 14 days after the order is entered. Certification dramatically raises the stakes for the company, which is why many cases settle shortly before or after this ruling. When a class is certified for trial, members get a notice explaining that they can opt out.

Very few class actions go to a jury. When the parties agree to settle, the deal is not final until a judge approves it, because the settlement will release the claims of people who were never in the room. Rule 23(e) lays out the process:

1. Preliminary approval. The judge reviews the proposed deal and decides it is likely to be approved, then orders notice to the class.
2. Notice and claims period. A settlement administrator emails or mails notices, launches the official settlement website, and accepts claims. The notice sets deadlines to file a claim, opt out, or object.
3. Fairness hearing. The court holds a hearing and may approve the deal only if it is "fair, reasonable, and adequate."
4. Final approval and judgment. The judge enters a final order, often along with rulings on attorneys' fees and service awards.

Under the Class Action Fairness Act, a federal court cannot grant final approval until at least 90 days after federal and state officials receive notice of the proposed settlement. The Google Assistant privacy settlement is a current example of this stage: its claim, opt-out, and objection deadline was August 27, 2026, and its final approval hearing is set for October 1, 2026, according to the official settlement website.

Final approval does not mean checks go out the next day. Under Federal Rule of Appellate Procedure 4, a notice of appeal in a civil case is generally due within 30 days after the judgment is entered. If anyone, often an objector, files an appeal, payments usually wait until the appeal is resolved.

The Facebook user privacy case shows how long that can take. The $725 million settlement was announced in December 2022, payouts were delayed until two appeals were resolved, and payments finally began going out in September 2025, according to Money and CBS News. Uncashed money from that first round funded a second distribution that began June 9, 2026.

Once the settlement is final, the administrator reviews claims, calculates each share, and pays by check or electronic payment. Our guides on checking a settlement's status and what to do if your check has not arrived cover this last stretch.

No two cases move at the same speed, but the order of events is consistent. The approximate durations below are general ranges, not rules, and complex cases can take much longer.

If a company harmed you in a way that seems larger than a typical class payout, such as a physical injury or major financial loss, you may have options beyond the class. A free case review takes about two minutes and connects you with independent attorneys who handle these cases. You can also browse lawsuits attorneys are investigating and open settlements.