How to Respond to a Complaint Letter Filed Against You

To respond to a complaint filed against you, read the document carefully, identify every allegation, and file a written answer with the court before your deadline. In federal court, that deadline is generally 21 days from the date you were personally served. Miss it, and the other side can ask the court to enter a default judgment giving them everything they asked for without hearing your side.¹

Everything else flows from that deadline. The steps below walk through what to check, what to preserve, and what your answer has to contain.

Check That You Were Properly Served

Before drafting anything, confirm the complaint reached you through a legally valid method. Under the federal rules, the summons and complaint must be served together, and the person handing them over must be at least 18 and not a party to the case.² Valid methods include personal hand-delivery, delivery to someone of suitable age at your home, or delivery to an authorized agent.

If the papers were left on your doorstep with no one home, or mailed without following proper procedure, you may have grounds to challenge service. Improper service is a defense, but you have to raise it in your first filing (your answer or a pre-answer motion). Skip it there and you lose it permanently.³

A plaintiff may also send you a written request asking you to waive formal service. Agreeing to the waiver buys you time: 60 days from the date the request was sent instead of 21.³ Refusing without good reason can result in the court making you pay the costs of formal service.²

Calculate Your Response Deadline

The deadline depends on the court and how you were served. In federal court you generally have 21 days after service to file your answer.³ If you waived formal service, you get 60 days from when the waiver request was sent, or 90 days if you are outside the United States. State courts set their own deadlines, commonly 20 to 30 days. The exact date is usually printed on the summons or stated near the top of the complaint.

Count every day after the day you were served, including weekends and holidays. If the last day falls on a Saturday, Sunday, or legal holiday, the deadline rolls to the next business day. If the clerk’s office is physically inaccessible on the final day (a weather emergency, for example), the deadline extends to the first day it reopens.⁴

Preserve Evidence Right Away

The moment you receive a complaint, you have a legal duty to preserve any documents, electronic files, or physical items that could be relevant to the case. This is sometimes called a litigation hold. Stop any routine deletion of emails, texts, backup tapes, or paper files that might relate to the dispute. Destroying relevant evidence, whether deliberately or through carelessness, can lead to sanctions or a jury instruction telling jurors to assume the missing evidence would have hurt your case.⁵

If you run a business, tell your IT department and any employees who may hold relevant records. The duty covers a wide range of material: emails, text messages, spreadsheets, calendar entries, photos, videos, voicemails, financial records, and paper documents. When in doubt, preserve it.

While you preserve, gather. Pull together the contracts, invoices, purchase orders, service agreements, and communications tied to the events in the complaint, and map each piece of evidence to the specific allegation it answers. If the complaint alleges a missed deadline, find the email or shipping record showing what actually happened. If a dollar figure is disputed, pull the invoices and payment records. Your answer will be stronger for being built on verifiable facts rather than blanket denials.

Draft Your Answer

Your answer is a formal legal document that responds to the complaint point by point. Start with the header: case number, party names exactly as they appear on the complaint, and the court or agency where the case is pending. Include contact information for you or your attorney.

If the complaint came from a government agency rather than a private party, check the agency’s website for a required response form. Administrative complaints often have their own formatting rules that differ from standard court filings.

Respond to Every Allegation

For each numbered allegation, you must do one of three things: admit it, deny it, or state that you lack enough information to know whether it is true.⁶ Lack of knowledge has the same legal effect as a denial. Any allegation you fail to address is treated as admitted, so do not skip any.

You can admit part of an allegation and deny the rest. If the complaint says you entered into a $50,000 contract and then failed to deliver, you might admit the contract existed but deny the failure to perform.⁶ Be specific. Vague or sweeping denials without a factual basis can be challenged.

A general denial (denying everything in the complaint) is only appropriate when you genuinely dispute every fact, including basic ones like your name and address. In most cases, specific denials are more credible and more defensible.

Raise Every Affirmative Defense

An affirmative defense is a reason you should not be held liable even if the facts in the complaint are true. You must include all of them in your answer, because leaving one out risks waiving it permanently. Common ones include:

Statute of limitations: the other party waited too long to sue.
Release: they previously signed an agreement releasing your liability.
Waiver: their conduct showed they gave up the right to enforce the claim.
Statute of frauds: the agreement had to be in writing but was not.
Res judicata: the same claim was already resolved in a prior case.

The federal rules list several recognized affirmative defenses, but the list is not exhaustive.⁶ When in doubt, include every defense that might apply. Raising one you end up not needing costs you nothing; losing one that could have won the case is fatal.

Certain procedural defenses have an even stricter rule. Lack of personal jurisdiction, improper venue, and insufficient service of process must appear in your first filing, whether that is your answer or a pre-answer motion. Miss them there and they are permanently waived.³

Include Any Compulsory Counterclaim

If you have your own legal claim against the plaintiff arising from the same events described in their complaint, you must include it as a counterclaim in your answer.⁷ This is called a compulsory counterclaim. Fail to raise it and you lose the right to bring it as a separate lawsuit later. If you are sued for breach of a contract and you believe the other party also breached that same contract, assert that claim now.

Permissive counterclaims, which arise from unrelated events, can be included but are not required. You can bring those as a separate case if you prefer.

Consider a Motion to Dismiss Instead

Sometimes a motion to dismiss is a better first move than an answer. A motion to dismiss argues that even if everything in the complaint were true, the case should be thrown out for a legal reason: the complaint fails to state a valid legal claim, the court lacks jurisdiction, or the case was filed in the wrong venue.³

Filing the motion generally pauses your answer deadline until the court rules. Win the motion and you may not need to file an answer at all. Lose it and you typically have 14 days after the ruling to answer.³ The approach works best when the complaint has obvious legal flaws, because it can resolve the case before full litigation.

If You Need More Time

If you cannot prepare a complete response by the deadline, ask the court for an extension before the deadline expires. Courts have broad discretion to grant extensions for good cause when the request comes in on time.⁴ File a written motion explaining why you need more time, or ask opposing counsel to agree to a short extension by stipulation.

Once the deadline passes, the standard gets harder. You must show excusable neglect, not simple inconvenience or oversight.⁴ Acting fast after you realize you missed the deadline improves your odds.

File and Serve Your Answer

Once your answer is complete, file it with the court and serve a copy on the opposing party. Most federal courts and many state courts require electronic filing through an online portal, which gives you instant confirmation. Where electronic filing is not available, file in person at the clerk’s office or send it by certified mail with a return receipt for a paper trail.

When you serve the other party by any method other than the court’s electronic filing system, include a certificate of service, a short statement confirming the date and method of delivery.⁸ Service through the court’s electronic system does not require a separate certificate. Keep copies of everything you file, along with any delivery confirmations.

Filing fees for an answer vary. Many courts do not charge defendants to file an answer, but some do. Check your court’s fee schedule, and if you cannot afford the fee, ask the clerk about a fee waiver application.

If You Already Missed the Deadline

Failing to respond in time allows the plaintiff to ask the clerk to enter a default against you.¹ Once default is entered, the plaintiff can seek a default judgment: a court order granting the relief they asked for without any input from you. If the claim is for a specific dollar amount, the clerk can enter judgment for that amount. Otherwise the plaintiff must apply to the judge, who may hold a hearing on damages.

A default judgment can be undone, but you have to act quickly. The court can set aside an entry of default for good cause.¹ If a final default judgment has already been entered, you can file a motion for relief, but the grounds are narrower. Valid reasons include:

Excusable neglect, such as a medical emergency or never receiving the documents.
Fraud or misconduct by the plaintiff in obtaining the judgment.
A void judgment, meaning the court lacked jurisdiction over you or the case.
Satisfaction, meaning the judgment has already been paid or otherwise resolved.

For excusable neglect, fraud, or newly discovered evidence, you must file the motion within one year after the judgment was entered.⁹ Other grounds require filing within a “reasonable time,” which courts read narrowly. The longer you wait, the harder it gets.

When to Bring in a Lawyer

Individuals can represent themselves (proceeding pro se), but businesses generally cannot. Corporations and LLCs almost always need a licensed attorney to appear in court. If you are responding on behalf of a business entity, hire counsel before the deadline passes.

Even as an individual, consider consulting an attorney when the complaint involves a large dollar amount, complex legal theories, or claims that could affect your property or professional license. An attorney can spot defenses and counterclaims you might overlook and make sure your answer meets every procedural requirement. Many attorneys offer limited-scope representation, reviewing and helping draft your answer without taking on the full case. If cost is a barrier, check whether your local bar association runs a lawyer referral service or legal aid program for people who qualify by income.

1
Cornell Law School. Federal Rules of Civil Procedure Rule 55 – Default and Default Judgment
2
Cornell Law School. Federal Rules of Civil Procedure Rule 4 – Summons
3
Cornell Law School. Federal Rules of Civil Procedure Rule 12 – Defenses and Objections
4
Cornell Law School. Federal Rules of Civil Procedure Rule 6 – Computing and Extending Time
5
Cornell Law School. Federal Rules of Civil Procedure Rule 37 – Failure to Make Disclosures or to Cooperate in Discovery
6
Cornell Law School. Federal Rules of Civil Procedure Rule 8 – General Rules of Pleading
7
Cornell Law School. Federal Rules of Civil Procedure Rule 13 – Counterclaim and Crossclaim
8
Cornell Law School. Federal Rules of Civil Procedure Rule 5 – Serving and Filing Pleadings and Other Papers
9
U.S. Court of International Trade. Federal Rules of Civil Procedure Rule 60 – Relief from a Judgment or Order