Free deadline calculator
Calculate your court or tribunal deadline.
Free, with no account needed. Choose what happened and when, and the deadline is calculated from the published rule, with deemed service, clear days and bank holidays applied. Every date shows the rule it came from, so you can check it yourself.
Keep the England and Wales civil defaults and go straight to what happened, or change the jurisdiction and forum first.
Free to calculate. Pro from £14.99 a month for saved matters, reminders and the audit-trail certificate. See the methodology.
See the rule, check it yourself
Every date shows its working.
A deadline you cannot check is a deadline you cannot rely on. Deadline Engine shows the trigger, every step of the count and the rule behind each one, so you can verify the date against the source in seconds rather than reconstruct it from scratch.
- The trigger the event that starts the clock
- Every step each part of the count, in order
- The rule the citation behind each step
- The final date with any weekend or bank-holiday roll-over
Acknowledgment of service, CPR Part 10
Claim form and particulars posted by first-class post, Wednesday 10 June 2026
The second business day after posting
CPR 6.1414 days to file the acknowledgment of service, counted from deemed service
CPR 10.3(1)26 June 2026 is a business day, so no roll-over is needed
CPR 2.8Illustrative example. Always verify against the rule and the facts of your matter.
A missed deadline is not a missed task.
In litigation the date is not admin. It is the difference between a live claim and a negligence file. Deadline Engine exists so the date is never the thing that goes wrong.
A claim struck out
Miss a filing date and the court can strike the statement of case out. The work is done; the claim is gone.
A limitation period lost
A missed limitation date cannot be recovered. There is no extension to apply for once it has passed.
A negligence exposure
A missed deadline is one of the most common professional-indemnity claims. The next conversation is with your insurer.
This is the problem Deadline Engine removes. Every date is computed from the published rule, cited, and kept as a record you can defend.
Determinism, not prediction
Why not just ask an AI?
Because a deadline you cannot trace is a deadline you cannot defend. A language model predicts a plausible answer; Deadline Engine computes the date from the published rule and shows its source.
A general AI assistant
- Predicts a plausible answer
- Can be confidently wrong
- Gives different answers to the same question
- Cannot show the rule it used
Deadline Engine
- Applies the published rule deterministically
- The same inputs always give the same date
- Cites the rule for every step
- Reviewable, so you can check it yourself
Every calculation, evidenced.
Pro turns a date into a defensible record. Save matters, get reminders and sync your calendar, and export an audit-trail certificate for any deadline, from £14.99 a month.
An audit-trail certificate for every deadline
Export any deadline as a PDF certificate: the trigger date, the rule applied, every step of the count, the public-holiday set and the rule edition in force. A defensible record for the file, the client and the insurer.
Sync to the calendar you already use
One click sends the deadline to Google Calendar, Outlook or Apple Calendar, with the citation attached.
Reminders before it counts
Email reminders at 14, 7 and 1 day before each deadline, sent to whoever owns the matter.
Every matter in one place
Save calculations to matters and see every upcoming deadline across your caseload, each with a record of how it was worked out.
Harwood v Lyle Logistics
File defence · CPR 15.4
Re: Calder Estates (possession)
Possession claim · Housing Act 1988
Okafor v BrightPath Ltd
Present ET1 · ERA 1996 s.111
Pearce & Co v HMRC
Notify appeal · TMA 1970 s.49G
Built for the people who carry the date.
If the deadline is your responsibility, it is your name on the file. Deadline Engine covers procedural deadlines across 13 practice areas, from CPR civil litigation to the Employment Tribunal, tax, immigration, family, insolvency and more.
Credible because it is checkable.
- Every date carries the citation for the rule it applied
- A deterministic engine: the same inputs always give the same date
- Encoded from primary sources and current to June 2026
- UK data residency; export or delete your data at any time
Deadline Engine is a Thesmios Ltd product (company number 17150638). It provides procedural information, not legal advice.
The questions practitioners ask
Every date is worked out from the published procedural rule, the same way every time, and shown with the rule it comes from. It is not a guess or an estimate. It provides procedural information, not legal advice, so always check the result against the rule and the facts of your matter.
The Civil Procedure Rules, the Family Procedure Rules, the tribunal rules and the other primary sources listed in the footer, encoded from the source and current to June 2026. Each result names the specific rule it applied.
Deadline Engine is not AI. A language model predicts a plausible answer and can be confidently wrong without showing its source. Deadline Engine applies the published procedural rule deterministically: the same inputs always produce the same date, and every step cites the rule it came from, so you can check the result yourself.
On a Pro account, each saved deadline can be exported as an audit-trail certificate (PDF): the trigger date, the rule applied, every step of the count, the public-holiday set used and the rule edition in force. It is a defensible record for the file, the client and, if it ever comes to it, your insurer.
Rules are re-verified against their primary source. On a Pro account, a saved matter can be recalculated when a rule or the public-holiday set changes, with a record of what changed and why.
No account is needed to calculate a deadline. If you save matters, your data is stored securely with UK data residency, and you can export or delete it at any time. See the privacy policy for detail.
No. Deadline Engine is a software tool that provides procedural information, not legal advice, and using it does not create a solicitor-client relationship.
Never let the date be the thing that goes wrong.
Save your matters, get a reminder before every deadline, and keep an audit-trail certificate for each date. Pro from £14.99 a month, with a 14-day free trial.
The calculator is free with no account. A card starts the trial, with no charge for 14 days. Cancel in one click; export your matters as .ics and CSV.