What counts as gross misconduct
Gross misconduct is conduct serious enough to break the trust at the heart of the job — so serious it can justify dismissal without notice for a first offence. Common examples:
- Theft, fraud or dishonesty
- Physical violence or serious threats
- Serious health-and-safety breaches
- Gross negligence causing (or risking) serious loss or harm
- Serious insubordination or refusing reasonable instructions
- Serious bullying, harassment or discrimination
- Being under the influence of drink or drugs at work
- Bringing the organisation into serious disrepute
A label doesn’t make it fairWhat an employer treats as gross misconduct should be listed in their disciplinary policy — but calling something “gross misconduct” doesn’t automatically make a dismissal fair. The conduct has to genuinely be that serious, and a fair process has to be followed.
Dismissal without notice
For genuine gross misconduct, an employer can carry out a “summary dismissal” — ending the job without notice or pay in lieu of notice. That’s the key difference from ordinary misconduct, where you’d normally get warnings first and your notice.
But “without notice” does not mean “on the spot”. An employer cannot lawfully march you out and sack you with no process. Even here, they must investigate and hold a fair disciplinary procedure first.
The fair procedure they must follow
In line with the ACAS Code of Practice, before dismissing for gross misconduct an employer should:
- Investigate reasonably and without unreasonable delay to establish the facts (they may hold an investigation meeting first).
- Write to you setting out the allegation and the possible outcome (including that dismissal is possible).
- Invite you to a disciplinary hearing with enough notice to prepare, and share the evidence.
- Let you be accompanied by a work colleague or a trade union representative.
- Genuinely consider your response before deciding — the decision must be reasonable.
- Confirm the decision in writing and give you the right to appeal to someone not previously involved.
Tribunals check the processIf an employer skips these steps, a dismissal can be unfair even where the conduct was serious — and a tribunal can increase compensation by up to 25% where the ACAS Code wasn’t followed.
Being suspended
An employer can suspend you while they investigate a serious allegation. But suspension:
- should be as brief as possible,
- is normally on full pay,
- is not a punishment and not a sign they’ve decided you’re guilty,
- should only be used where there’s a genuine reason (protecting the investigation, colleagues or customers).
If you’re suspended: keep it confidential, cooperate with the investigation, keep your own records, and get advice from ACAS or your union.
If you think it was unfair
If the punishment was too harsh, you didn’t do it, or the process was unfair, you can challenge it:
- Appeal internally first — always use the appeal.
- If that fails and you have the qualifying service (usually 2 years, though some reasons need no qualifying period), you can start ACAS early conciliation and potentially bring an unfair dismissal claim.
- The tribunal deadline is strict: 3 months less a day from the dismissal.
Do this now
Ask for the allegation and evidence in writing, prepare your response, and use your right to be accompanied at the hearing. Get free, confidential advice from ACAS (0300 123 1100) or Citizens Advice before it.
Already dismissed? See unfair dismissal for your options, or if you’re offered a deal to leave quietly, understand a settlement agreement before you sign.
Related guides — work & rights
Source verification
Primary sources: ACAS — the Code of Practice on disciplinary and grievance procedures, Dismissals / Types of dismissal, and the Disciplinary procedure step-by-step; plus GOV.UK — Dismissal: your rights (
gov.uk/dismissal). Last verified 2 July 2026 — that gross misconduct can justify dismissal without notice for a first offence (examples: theft/fraud, violence, serious H&S breaches, gross negligence, serious insubordination), that a fair procedure (investigation, written allegation, disciplinary hearing with the right to be accompanied, reasonable decision, written outcome, appeal) must still be followed under the ACAS Code, that suspension should be brief and normally on full pay and is not a punishment, and the unfair-dismissal route (usually 2 years’ service; 3-months-less-a-day tribunal deadline via ACAS early conciliation) were web-checked against ACAS and GOV.UK. Confidence: High — long-standing procedure under the ACAS Code (tribunals can adjust awards by up to 25% for unreasonable non-compliance). Scope: Great Britain (Northern Ireland has equivalent rules via the LRA). Not legal advice — free help from ACAS (
0300 123 1100) and Citizens Advice.
Gross misconduct — common questions
What is gross misconduct?
Behaviour serious enough to break the trust in the job and justify dismissal without notice, even for a first offence — theft, fraud, violence, serious H&S breaches, gross negligence, serious insubordination, serious bullying/harassment, being under the influence at work. It should be listed in the disciplinary policy.
Can I be sacked on the spot?
No. An employer can dismiss without notice (summary dismissal) for genuine gross misconduct, but can’t lawfully sack you with no process — they must investigate, put the allegation to you, hold a hearing where you can respond and be accompanied, and give an appeal.
What’s the fair procedure?
Reasonable investigation, written allegation, a disciplinary hearing with notice and the right to be accompanied, a reasonable decision, written outcome, and a right of appeal — following the ACAS Code. Skipping it can make the dismissal unfair.
Can I be suspended?
Yes, while they investigate — but it should be brief, normally on full pay, only where there’s a genuine reason, and it’s not a punishment or a finding of guilt.
What if it was unfair?
Appeal internally first. If that fails and you have the service (usually 2 years; some reasons need none), use ACAS early conciliation and consider an unfair dismissal claim — deadline 3 months less a day. Get advice from ACAS or Citizens Advice.