Three-Month Rule for Discrimination Claims (Employment Tribunal)

Discrimination claims in the Employment Tribunal are subject to strict statutory time limits. The most important is the “three-month rule”, which generally requires claims under the Equality Act 2010 to be presented within three months less one day of the discriminatory act complained of.

This rule applies to claims involving discrimination, harassment, and victimisation in employment and related work situations. It is enforced through tribunal procedure rules and supported by statutory provisions in the Equality Act 2010, particularly section 123.

Missing the deadline can result in a claim being rejected unless the tribunal decides it is just and equitable to allow it to proceed out of time.

Legal Basis of the Three-Month Rule

The three-month limitation period is set out in:

• Equality Act 2010, section 123
• Employment Tribunal Procedure Rules (which govern filing requirements)

The Equality Act 2010 provides that an Employment Tribunal must not consider a complaint unless it is brought within the limitation period, unless an extension is granted.

This rule applies across all protected characteristics, including:

• Age
• Disability
• Sex
• Race
• Religion or belief
• Sexual orientation
• Gender reassignment
• Pregnancy and maternity
• Marriage and civil partnership

What the Three-Month Rule Means in Practice

Standard limitation period

Most discrimination claims must be submitted:

Within 3 months minus 1 day

This applies to:

• Direct discrimination
• Indirect discrimination
• Harassment
• Victimisation
• Failure to make reasonable adjustments

The rule applies whether the claimant is an employee, worker, job applicant, or former employee.

When the Time Limit Starts

The starting point depends on the nature of the conduct.

Single discriminatory act

Time runs from the date of the act, for example:

• A refusal of promotion
• An act of harassment on a specific date
• A discriminatory dismissal decision

Ongoing or continuing discrimination

Where conduct forms part of a continuing situation, time may run from:

• The last act in a series of linked discriminatory acts

This is important in cases involving:

• Ongoing harassment
• Repeated failure to make reasonable adjustments
• Systemic workplace discrimination

Tribunals assess whether incidents are genuinely linked or are separate, isolated events.

Delayed consequences

In some situations, the discriminatory decision occurs earlier than its impact. The limitation period normally runs from the date of the discriminatory act itself, not the later consequences.

ACAS Early Conciliation and Its Effect on Time Limits

Before issuing an Employment Tribunal claim, the claimant must notify the Advisory, Conciliation and Arbitration Service (ACAS) and engage in Early Conciliation.

This process affects limitation periods in two main ways:

1. Pause of the limitation clock

When ACAS is notified:

• The limitation period is paused
• The pause lasts until ACAS issues a certificate

This ensures claimants are not disadvantaged while settlement discussions take place.

2. Post-certificate extension

After the Early Conciliation Certificate is issued:

• The claimant usually has at least one month from the certificate date to submit the claim, if time would otherwise have expired sooner

Important constraint

Early conciliation only preserves time if ACAS is contacted before the limitation period expires. If the deadline has already passed, conciliation does not revive the claim.

“Just and Equitable” Extensions

If a discrimination claim is filed late, the tribunal has discretion to extend time under the “just and equitable” test.

This is a broad but structured discretion under section 123 of the Equality Act 2010.

Factors considered by tribunals include:

• Length of delay
• Reasons for delay
• Whether the claimant knew about the time limit
• Whether evidence is still available
• Prejudice to the employer
• Overall fairness in the circumstances

There is no automatic right to an extension. Tribunals apply this discretion carefully and often refuse extensions where delays are significant or unexplained.

Continuing Acts: Why They Matter

A key issue in discrimination cases is whether conduct is:

• A single act, or
• A continuing act or course of conduct

Where a continuing act is established, the tribunal may treat all related events as in time if the claim is brought within three months of the final act.

However:

• Isolated incidents are not usually treated as part of a continuing act
• Employers often argue that incidents are separate and time-barred
• The tribunal decides based on the overall factual pattern

Interaction With Internal Procedures

Internal processes such as:

• Grievances
• Disciplinary appeals
• HR investigations

do not extend the three-month limitation period.

A claimant must still ensure that:

• ACAS is notified in time
• The tribunal claim is issued within the limitation period (as adjusted by ACAS pause rules)

Common Misunderstandings About the Three-Month Rule

1. Believing the clock starts at resignation or dismissal

It normally starts at the discriminatory act, not when employment ends.

2. Assuming internal complaints stop time running

They do not affect limitation periods.

3. Assuming ACAS always extends time

It only pauses time; it does not revive expired claims.

4. Treating all repeated conduct as a continuing act

Tribunals apply strict analysis to determine whether events are legally connected.

Practical Consequences of Missing the Deadline

If the three-month rule is not met:

• The tribunal may refuse to hear the claim
• Evidence may still exist but become legally irrelevant
• Settlement leverage is significantly reduced
• The respondent can raise limitation as a complete defence

Even strong discrimination claims may fail purely due to timing issues.

Key Takeaways

The three-month rule for discrimination claims requires most Equality Act 2010 claims to be filed within three months less one day of the discriminatory act. The limitation period can be affected by continuing acts and is paused during ACAS Early Conciliation, provided ACAS is contacted in time. Tribunals have discretion to allow late claims if it is just and equitable, but this is applied cautiously. Correct identification of the start date and strict compliance with deadlines are essential to preserving the right to bring a claim.