Written Warning Letter Template
A written warning documents a formal disciplinary step under the ACAS Code of Practice — used when conduct or performance falls short and needs to be addressed and improved.
What this written warning letter covers
- The reason for the warning
- The improvement required and review period
- Consequences of further issues
- How long the warning stays on file
- The employee's right of appeal
When you need a written warning letter
- Informal conversations haven't resolved a conduct or performance issue
- Following a formal disciplinary meeting
- Before considering dismissal, as part of a fair process
The legal framework
Understanding the law behind a written warning helps you use it well. Here is the key UK legislation and guidance that applies:
Frequently asked questions
Do I have to follow a set process before dismissing someone?
Yes, in effect. Employment tribunals apply the ACAS Code of Practice on Disciplinary and Grievance Procedures, and can increase compensation by up to 25% if an employer unreasonably fails to follow it — a documented written warning is a key part of a fair process.
What's the difference between a first and final written warning?
A first written warning is usually the first formal step after informal conversations haven't resolved the issue. A final written warning is more serious — often issued after a prior warning, or for more serious misconduct — and makes clear that dismissal may follow if there's no improvement.
How Legal Lift helps
Answer a few plain-English questions and our AI generator produces a tailored written warning letter, ready to edit, download as PDF or Word. Every template is kept current with UK law, and our SRA-regulated solicitor partners are available if you'd like it reviewed.