If a tribunal letter or an email from the Employment Tribunal has just landed with a claim form attached, you are probably worried and short of time. That is normal. This guide explains what an ET1 claim is, what you must do in the first 48 hours, and which deadline matters most.

This page is general information for employers in England, Wales and Scotland. It is not legal advice about your case.

What is an ET1 claim?

The ET1 is the form an employee, former employee or worker uses to start a claim in the Employment Tribunal. Common claims include unfair dismissal, discrimination, unpaid wages or holiday pay, redundancy pay and breach of contract. When the tribunal accepts the claim, it sends a copy to the employer, called the respondent, together with instructions on how and when to reply.

Your first 48 hours: a practical checklist

1. Find the date the tribunal sent the claim. It is on the covering letter or email. Your response deadline runs from that date, not from the day you opened the post.

2. Diarise the response deadline immediately. The usual period is 28 days. See our guide to the ET3 response deadline.

3. Read the whole ET1. Note each claim type, the dates mentioned and what the employee says they want (compensation, reinstatement, a declaration).

4. Check whether Acas early conciliation took place. Most claimants must contact Acas first. Read our guide to Acas early conciliation for employers.

5. Stop deleting anything. Preserve emails, messages, rotas, payroll records, contracts, policies, disciplinary and grievance notes and anything else linked to the claim. Tell managers involved not to discuss the claim with the employee or delete records.

6. Identify who needs to know. Limit it to the people who must help you respond, and keep notes of who has seen what.

7. Collect the key documents in one folder: contract, handbook extracts, performance and disciplinary history, dismissal letter, appeal outcome and any settlement discussions.

8. Decide how you will be represented. You can respond yourself, use an employment law adviser or instruct a solicitor. Make the decision early, because the response needs facts, dates and legal arguments that are hard to rebuild in the last days.

The deadline that matters most: the ET3 response

Your reply is called the ET3. The standard time limit is 28 days from the date the tribunal sent you the claim. Missing it can lead to a default judgment against you, which means the tribunal can decide the claim without hearing your side. Late responses can be accepted, but you need to ask for an extension and give reasons, and the tribunal may refuse.

Five mistakes employers make after receiving an ET1

• Ignoring the claim because it looks weak. A claim that seems weak on paper can still succeed if you do not respond.

• Contacting the employee informally to "sort it out". Use proper channels, such as Acas conciliation or a written settlement offer.

• Missing a part of the claim. The ET1 can contain several claims. A response that deals with only one risks default judgment on the others.

• Relying on memory. Reconstruct events from documents and dates, not recollection.

• Leaving it until the last week. Witness statements, documents and legal arguments take longer than most employers expect.

Can the claim be settled?

Often, yes. Settlement can happen at any stage, through Acas conciliation or directly between the parties. A settlement reached through Acas is recorded on a COT3 form. Whether settling is sensible depends on the strength of the claim, the cost of defending it and the risk to your reputation. A specialist can assess this before you decide.

When to get specialist help

Get advice quickly if the claim includes discrimination (compensation is not capped), if a senior employee or key witness is involved, if you did not follow a fair process, or if you are close to the 28-day limit.