An acknowledgement of service is a short court form a defendant files to confirm they have received a claim, without admitting any part of it. Under the Civil Procedure Rules in England and Wales, you generally have 14 days from service of the claim form to file it, and doing so extends your deadline to file a full defence from 14 days to 28 days after service of the particulars of claim. It also preserves your right to argue that the court should not be hearing the case at all.
Why File One
There are two practical reasons a defendant files an acknowledgement of service rather than going straight to a defence.
The first is time. CPR Part 10 says a defendant who cannot file a defence within the initial 14-day window should file the acknowledgement instead, which pushes the defence deadline out to 28 days after service of the particulars of claim. For a complex dispute or one that turns on technical evidence, those extra two weeks are the difference between a considered defence and a rushed one.
The second is jurisdiction. A defendant who wants to argue that the court has no authority to hear the case must file an acknowledgement of service first, then bring the challenge under CPR Part 11.
Filing the form is not an admission of liability and does not signal that you accept the court’s authority. It is a procedural step that keeps your options open.
What the Form Asks For
The standard form in England and Wales is the N9. It is short, but every field matters because errors cause delays. You will need to give:
- Your full name, corrected if it differs from the claim form.
- An address for service, either a solicitor’s business address or your own residential or business address within the United Kingdom.
- Contact details: telephone, fax, email, and DX number if applicable.
- A tick-box response indicating whether you admit the claim, intend to defend all of it, intend to defend part of it, or intend to contest jurisdiction.
- Your date of birth and signature.
The tick box is the most consequential part of the form. “Contest jurisdiction” starts a separate procedure under CPR Part 11. “Defend all” or “defend part” starts the clock on filing a full defence. Leaving it blank, or choosing the wrong option, creates problems that are harder to fix later.
The 14-Day Deadline
The general rule under CPR Part 10 is that the acknowledgement must be filed within 14 days after service of the claim form. If the claim form says the particulars of claim will follow separately, the 14 days run from service of those particulars instead. The count begins the day after service. Weekends and bank holidays are included, unless the final day falls on one, in which case the deadline moves to the next business day.
How This Extends Your Defence Deadline
Without an acknowledgement on file, you must file a full defence within 14 days of receiving the particulars of claim. With one on file, that deadline becomes 28 days. That is the practical payoff, and for most defendants it is the reason to file.
Contesting the Court’s Jurisdiction
A jurisdiction challenge follows a strict sequence. Under CPR Part 11, you first file an acknowledgement of service and tick the box for contesting jurisdiction. Then, within 14 days of filing that acknowledgement, you must make a formal application supported by evidence explaining why the court lacks jurisdiction.
The trap is timing. If you file the acknowledgement but fail to make the jurisdiction application within 14 days, the court treats you as having accepted its authority. The right to object is gone. This is one of the few points in civil procedure where a missed deadline permanently closes a door rather than simply causing inconvenience.
What Happens If You Miss the Deadline
If you neither file an acknowledgement of service nor file a defence within the 14-day window, the claimant can ask the court for default judgment. Default judgment means the court decides the case without hearing from you. For money claims, the claimant can often obtain it by filing a request form. There is no hearing, and you get no say in the outcome.
Default judgment is not available in every situation. It cannot be entered in claims governed by the Part 8 procedure, in certain consumer credit disputes, or where the defendant has already applied to strike out the claim or for summary judgment. But for ordinary debt and damages claims, the process is fast and largely automatic.
Setting a Default Judgment Aside
A defendant who has had judgment entered against them by default can apply under CPR Part 13 to have it set aside. The court will grant the application if you show a real prospect of successfully defending the claim, or some other good reason why the judgment should be reversed. The court also weighs whether you acted promptly after learning about the judgment. Waiting weeks or months makes success significantly less likely.
Where the original service was defective, for example the claim form went to the wrong address, the court must set the judgment aside regardless of the merits. Where you simply forgot or ignored the paperwork, the burden is much higher.
What Comes After Filing
Your next move depends on which box you ticked. If you indicated an intent to defend, you must file a full defence within 28 days of service of the particulars of claim. The defence should respond to each allegation. Ignoring specific allegations is risky, because the court may treat silence as an admission on that point.
Settlement or mediation can be raised at any stage, and the acknowledgement itself sometimes prompts a more realistic conversation between the parties once both sides know the defendant is engaged. Legal advice is worth getting early: the form is simple, but the decisions it triggers carry consequences that are hard to undo once the deadlines pass.
A Note on U.S. Federal Cases
American federal courts do not use an “acknowledgement of service.” The closest equivalent under Federal Rule of Civil Procedure 4(d) is a waiver of service, which works differently: the plaintiff mails the complaint with a request to waive formal service, and a defendant who signs gets 60 days from the date the request was sent to file an answer, or 90 days if located outside the United States. A defendant who refuses without good cause can be ordered to pay the costs of formal service. If your case is in U.S. federal court, the rules and deadlines described above do not apply to you.