Can An Employer Stop Staff Working For A Competitor?

Priya runs a design agency in Manchester. One of her senior account managers resigns, and a week later Priya sees an update on LinkedIn: they're joining a rival agency that pitches for the same clients.

Her first thought is understandable: can she stop them?

The answer depends on what your employment contract says, how carefully the restrictions were drafted, and what business interest you're trying to protect. UK law won't usually let you stop someone earning a living just because you don't like where they're going. But it can protect your confidential information, client relationships, workforce stability and goodwill where the restriction is reasonable.

Let's look at what to check before you send a warning letter or decide your next step.

Can You Stop An Employee Working For A Competitor?

It depends. You can only stop a departing employee working for a competitor if you have an enforceable restriction that goes no further than reasonably needed to protect your business.

These clauses are usually called restrictive covenants or post-termination restrictions. They sit in an employment contract and apply after employment ends.

A court will generally start from the position that a restraint of trade is unenforceable unless you can show it protects a legitimate business interest and is reasonable. In plain English, you need a real business reason, not just a preference that the employee doesn't join a rival.

Legitimate interests can include:

• Confidential information, such as pricing models, product roadmaps, supplier terms or sensitive strategy documents.
• Client connections, especially where the employee had direct influence over key customers.
• Workforce stability, where the employee may try to take team members with them.
• Goodwill, particularly in relationship-led businesses such as agencies, consultancies, recruitment firms and professional services.

If you don't have a written restriction, you may still have some protection during the notice period and around confidential information. Employees owe duties during employment, and senior employees can owe stronger duties. But once employment has ended, your position is usually much stronger if the contract is clear, signed and tailored to the role.

Is Your Non-Compete Clause Enforceable In The UK?

A non-compete clause is only enforceable if it's reasonable, and it's usually the hardest type of restriction to rely on.

A non-compete tries to stop the employee working for, being involved with, or setting up a competing business for a period after they leave. Because it directly affects their ability to work, UK courts look at these clauses closely.

When assessing a non-compete, the main questions are usually:

• Duration: Is the period reasonable for the employee's role and access to sensitive information?
• Geography: Is the area narrow enough, or does it block too much of the market?
• Scope: Does it stop only competing activities, or does it stop any role at a competitor?
• Seniority: Did the employee have influence over clients, pricing, strategy or staff?
• Timing: Was the clause reasonable when the employee signed the contract, not just when they left?

For example, Mike runs a recruitment agency in Leeds. His sales director has a contract that says she can't work for any recruitment business anywhere in the UK for 12 months after leaving. That may be too wide, especially if the agency works only in healthcare recruitment across the North of England.

A narrower clause might have a better chance. For instance, a 3 month restriction on working in healthcare recruitment for named competitors, combined with a 6 month non-solicitation clause for clients the director personally dealt with in the last 12 months, may be easier to justify. The exact answer still depends on the facts.

The UK Government has previously announced plans to limit non-compete clauses in employment contracts to 3 months, but you should check the current position before relying on a longer restriction. Even without a statutory cap, the usual reasonableness test still matters.

What Other Restrictions Can Protect Your Business?

Other restrictions may protect your business more effectively than a non-compete, and they're often easier to justify.

A full ban on joining a competitor can feel like the strongest option, but it isn't always the most enforceable. If your real concern is client contact, a non-solicitation or non-dealing clause may be a better fit.

Non-Solicitation Clauses

A non-solicitation clause stops the former employee approaching certain clients, customers or suppliers after they leave. It usually needs to be limited to people or businesses the employee had material dealings with during a defined period, such as the last 6 or 12 months of employment.

Non-Dealing Clauses

A non-dealing clause goes further. It stops the former employee dealing with certain clients even if the client approaches them first. Because this is broader, it needs careful drafting.

Non-Poaching Clauses

A non-poaching clause stops the former employee encouraging your staff to leave. This can be useful where a senior person manages a team or has influence over employees and contractors.

Confidentiality Clauses

A confidentiality clause protects information that isn't public and has commercial value. This can continue after employment ends, but it must be clear about what information is protected.

Garden Leave Clauses

Garden leave keeps the employee employed during their notice period but away from clients, systems and the workplace. You usually need a contract clause that lets you do this, and you must keep paying salary and benefits during garden leave.

If the employee has a 3 month notice period and a 3 month post-termination restriction, the contract should say whether time on garden leave reduces the later restriction. Courts can be cautious about restrictions that, in reality, keep someone out of the market for too long.

What Should You Do When An Employee Is Leaving To A Competitor?

Act quickly, but don't rush into threats before you've checked the contract and the facts.

A measured first response helps you protect the business without making the situation worse. It also gives you a better record if you later need to ask for undertakings or urgent help from a disputes lawyer.

1. Find the signed contract: Check the exact version the employee signed, including any promotions, updated terms or side letters.
2. Check the notice period: If there's no contractual notice, employees who have worked for at least one month usually need to give at least one week's notice under the Employment Rights Act 1996. Many contracts require more.
3. Review each restriction: Look at the duration, geography, client scope, competitor scope and the employee's actual role.
4. Secure business property: Ask for return of laptops, phones, access cards, documents, samples and storage devices.
5. Cut off access at the right time: Remove access to email, CRM systems, shared drives, project tools and password managers when appropriate.
6. Preserve evidence: Keep copies of relevant emails, system logs, resignation messages, client communications and any suspicious downloads.
7. Remind them of obligations: Send a calm letter setting out the restrictions, confidentiality duties and return-of-property requirements.
8. Consider the new employer: In some cases, a carefully drafted letter to the new employer can help prevent misuse of your information. Get advice first, as heavy-handed letters can backfire.
9. Ask for undertakings: You may ask the employee to confirm, in writing, that they won't contact protected clients, use confidential information or breach the restrictions.

Time can matter if you need an interim injunction, because delay can weaken your position. If court action is on the table, you may need a specialist disputes lawyer who can advise on urgent injunctions and representation.

How Do Confidential Information And Client Lists Fit In?

Confidential information can be protected even where a non-compete is weak, but you still need to be clear about what information is genuinely confidential.

Not everything an employee learns at work is confidential. General skill, experience and know-how usually belongs to the employee. Your protected information is more likely to include material such as:

• client lists that aren't publicly available
• pricing, margins and discount structures
• sales pipelines and renewal dates
• product plans and technical specifications
• supplier terms and negotiated rates
• marketing strategy and tender documents
• internal playbooks, scripts and processes that give you a commercial edge

Client lists can also involve personal data, especially if they include names, email addresses, phone numbers, preferences or notes about contacts. That means the UK GDPR and Data Protection Act 2018 may be relevant if an employee downloads, emails or takes that data without authority.

If you suspect data has been taken, keep a clear record of what happened and who was affected. You may need to assess whether there has been a personal data breach and whether it needs to be reported to the Information Commissioner's Office. Not every incident is reportable, but you should make that decision promptly and document your reasoning.

Say Priya finds that her departing account manager exported 400 CRM contacts two days before resigning. She should avoid deleting evidence or accessing the employee's personal accounts. Instead, she should preserve system logs, disable CRM access, check what data was exported, ask for deletion and non-use undertakings, and get tailored advice on privacy and employment issues.

Restrictive Covenant Template: What To Include

A restrictive covenant clause should be tailored to the role, because a one-size-fits-all template can easily become too wide to enforce.

If you're reviewing your employment contracts, use this outline as a starting point for what the clauses should cover. A lawyer should tailor the wording before you use it, especially for senior employees, sales staff, technical staff and client-facing roles.

1. Role And Seniority: State the employee's role, responsibilities and access to clients, staff and confidential information.
2. Legitimate Business Interests: Identify what you're protecting, such as confidential information, client relationships, suppliers or workforce stability.
3. Confidential Information: Define the categories of confidential information and make clear the duty continues after employment ends.
4. Return Of Property: Require return or deletion of documents, devices, data, passwords, access tokens and copies.
5. Non-Solicitation: Limit the clause to clients, prospective clients or suppliers the employee had meaningful dealings with during a set look-back period.
6. Non-Dealing: Use this only where needed, and limit it to the relationships that matter to the business.
7. Non-Compete: Keep the activity, duration and territory as narrow as possible, and explain why lesser restrictions aren't enough.
8. Non-Poaching: Limit it to employees, contractors or senior team members the departing employee worked with or managed.
9. Garden Leave: Set out when you can place the employee on garden leave and whether it reduces any post-termination restriction.
10. Remedies And Undertakings: State that you may seek written undertakings and other remedies if the restrictions are breached.
11. Review Points: Update the restrictions when the employee is promoted, changes teams or gains access to more sensitive information.

If you introduce new restrictions after employment has started, handle the change carefully. You may need consultation, clear written agreement and something of value in return. For a senior promotion, the promotion itself may support updated restrictions if the new terms are properly documented.

Also make sure the contract is consistent with your practical systems. If everyone can download the full client list at any time, it becomes harder to show you treated it as confidential. Access controls, password policies, CRM permissions and employee offboarding checklists all support your legal position.

Key Takeaways

• You can only stop a former employee joining a competitor if the restriction is reasonable and protects a legitimate business interest.
• Non-compete clauses are usually harder to enforce than non-solicitation, non-dealing, confidentiality and non-poaching clauses.
• Check the signed contract, notice period, role, client access and evidence before sending a warning letter.
• Client lists and CRM exports may raise confidentiality and UK GDPR issues, so preserve evidence and assess the privacy risk promptly.
• Restrictive covenants work best when they're tailored to the employee's role and reviewed when that role changes.

If you'd like help with your employment contracts, restrictive covenants, confidentiality clauses or offboarding process, you can reach us at 08081347754 or team@sprintlaw.co.uk for a free, no-obligations chat.