What counts as a fair dismissal in the UK?

## The short answer

In the UK, a dismissal is only fair if two things are true: the employer has a reason that the law recognises as potentially fair, and the employer acts reasonably in treating that reason as sufficient, including following a fair procedure. There are five potentially fair reasons: conduct, capability, redundancy, statutory illegality, and some other substantial reason. Even with a valid reason, an unfair process can make the dismissal unfair. Employees generally need a qualifying period of continuous service to claim ordinary unfair dismissal, but some dismissals are automatically unfair from day one.

## The five potentially fair reasons

- **Conduct.** Misconduct such as theft, persistent lateness, or breach of policy. Gross misconduct can justify dismissal without notice, but only after a fair investigation.

- **Capability or qualifications.** The employee cannot do the job to the required standard, or lacks necessary qualifications. This includes long-term ill health, which must be handled with particular care.

- **Redundancy.** The role, not the person, is genuinely no longer needed, or fewer people are needed for that work.

- **Statutory illegality.** Continuing to employ the person would break the law — for example, a driver who loses their licence or a worker without the right to work.

- **Some other substantial reason (SOSR).** A genuine, substantial reason not covered above, such as a serious irreconcilable workplace conflict or a justified business reorganisation falling short of redundancy.

## Reason alone is not enough

Having a valid reason is only half the test. The employer must also act reasonably, which means following a fair procedure appropriate to the reason. For most cases this draws on the principles in the relevant statutory code of practice on discipline and grievance. Skipping the process is the most common way an otherwise justifiable dismissal becomes unfair.

A fair procedure typically involves:

- A proper investigation before any decision.

- Telling the employee the allegation or concern in writing, with the evidence.

- A meeting at which they can respond, with the right to be accompanied.

- A decision made by someone with an open mind.

- A right of appeal to a different, more senior person where possible.

## Dismissals that are automatically unfair

Some reasons make a dismissal automatically unfair regardless of service length or process. These include dismissing someone for whistleblowing, for asserting a statutory right, for pregnancy or taking family leave, for trade union membership or activity, or for reasons connected to certain protected characteristics. If a dismissal touches any of these, the usual qualifying period does not protect the employer, and discrimination claims can run alongside with uncapped compensation.

## Capability and ill health: handle with care

Dismissing for poor performance requires giving the employee a genuine chance to improve — clear standards, support, and time. Dismissing for ill health requires up-to-date medical evidence, consultation with the employee, and consideration of reasonable adjustments, because a health condition may amount to a disability. Rushing either route is a frequent source of successful claims.

## Redundancy is a process, not a label

Calling a dismissal a redundancy does not make it one. There must be a genuine reduction in the need for that work, a fair and objective selection method, meaningful consultation, and consideration of suitable alternative roles. Larger-scale redundancies trigger additional collective consultation duties with their own timescales.

## Common employer mistakes

- Deciding the outcome before the investigation or hearing.

- Treating gross misconduct as automatic dismissal without investigating.

- Failing to offer an appeal.

- Using "redundancy" to remove a specific individual.

- Ignoring the possibility that a health condition is a disability.

## Keeping the process defensible

The difference between a fair and an unfair dismissal is often documentation: dated investigation notes, the letters sent, the minutes of meetings, and the appeal outcome. When these are scattered across inboxes and managers' notebooks, defending a claim becomes difficult even when the employer acted reasonably. Centralising case records with a clear chronology is one of the simplest ways to reduce risk. Neart.ai builds enterprise-grade HR and payroll tooling intended to keep this kind of audit trail consistent across managers and locations.

## Practical takeaway

Before dismissing anyone, ask two questions: is my reason one of the five the law recognises, and have I followed a fair, well-documented process for that reason? If either answer is shaky, pause. A genuine reason undermined by a rushed process is the classic recipe for a successful unfair dismissal claim — and the fix is almost always procedure, not haste.