I signed a non-compete clause, is it enforceable?

Post-termination restrictive covenants (including non-compete, non-solicitation, non-dealing, and non-poaching clauses) are restraints of trade. Under English law, they are prima facie void as contrary to public policy. They will only be enforceable if they go no further than is reasonably necessary to protect a legitimate proprietary interest of the employer.

Legitimate interests typically include: trade secrets and confidential information; customer relationships; and (in some cases) key employee relationships. The employer must show they have a genuine interest to protect.

The scope of the restriction must be proportionate to that interest. Courts will assess: duration (6–12 months is common for senior employees; longer periods are harder to justify); geographical scope (must be limited to the area in which the employee actually operated); and activity scope (must be limited to activities genuinely competitive with the employer's business).

Courts will not rewrite an unenforceable clause to make it enforceable — they will either enforce it as written or strike it out. Some agreements include "severance" clauses allowing parts to be removed if necessary.

If you are considering working for a competitor, you should: (1) obtain a copy of your contract and identify any restrictive covenants; (2) seek legal advice on their enforceability given your specific role, length of service, seniority, and the scope of the restriction; (3) consider whether the new role actually breaches the clause as written.

Breach of an enforceable non-compete can lead to an injunction preventing you from starting the new role and a claim for damages.