A Grievance Letter is a formal written complaint submitted by an employee in England and Wales to their employer to raise a concern about their treatment at work, a breach of their employment contract, or a violation of their legal rights. It is the first formal step in the statutory grievance procedure set out in the ACAS Code of Practice on Disciplinary and Grievance Procedures, which applies to all employers in England, Scotland, and Wales.

The ACAS Code of Practice on Disciplinary and Grievance Procedures — issued under Section 199 of the Trade Union and Labour Relations (Consolidation) Act 1992 — sets out minimum standards of fairness that employers must follow when handling grievances. While the Code is not legally binding in the same way as an Act of Parliament, Employment Tribunals are required to take it into account in relevant proceedings. Under Section 207A of TULRCA 1992, an Employment Tribunal may increase any award it makes by up to 25% where the employer has unreasonably failed to follow the Code, and may reduce an award by up to 25% where the employee has unreasonably failed to follow it.

A formal grievance letter sets the statutory grievance process in motion. On receipt of a formal grievance, the employer is required under the ACAS Code to acknowledge receipt promptly, carry out a reasonable investigation, invite the employee to a grievance meeting (at which the employee has the right to be accompanied under Section 10 of the Employment Relations Act 1999), provide a written decision after the meeting, and allow the employee to appeal against the outcome.

A grievance letter can cover a wide range of workplace issues, including: bullying or harassment; discrimination under the Equality Act 2010; unfair treatment or victimisation; a breach of the employment contract; an unlawful deduction from wages; a health and safety concern; a failure to make reasonable adjustments for a disability; or a failure by the employer to follow its own procedures. The common thread is that the employee is formally putting the employer on notice of a complaint and requiring the employer to address it in accordance with a fair and transparent process.

A well-drafted grievance letter is also important as a precursor to an Employment Tribunal claim. Before a claim is issued, ACAS Early Conciliation is required. A formal grievance letter creates a contemporaneous record of the complaint, demonstrates the employee's attempts to resolve the matter internally, and strengthens the employee's legal position.

A formal grievance letter is appropriate whenever an employee in England and Wales has a serious concern about their treatment at work that has not been resolved — or cannot appropriately be resolved — through informal means.

The ACAS Code of Practice encourages employees to resolve minor grievances informally in the first instance, for example by speaking directly to their line manager or to a more senior manager. Informal resolution is quicker, less adversarial, and often more effective at preserving the working relationship. However, there are many situations in which raising a grievance informally is impractical or has already been attempted without success: where the grievance is about the employee's direct line manager, making it impossible to raise the matter informally with that person; where a previous informal attempt to resolve the issue has been dismissed or ignored; where the matter is sufficiently serious — for example, involving allegations of harassment, discrimination, or a criminal act — to require formal investigation from the outset; or where the employee is concerned about retaliation and wishes to create a formal record of the complaint before the situation escalates.

A formal grievance letter is particularly important in the following circumstances. First, where an employee is considering bringing a claim to an Employment Tribunal: raising a formal internal grievance before lodging a Tribunal claim is not strictly a legal requirement (unlike the previous statutory dispute resolution procedures that were repealed in 2009), but failure to do so may result in a reduction of up to 25% in any Tribunal award under Section 207A of TULRCA 1992. Second, where an employee wishes to protect themselves against victimisation: the act of raising a grievance is a protected act under the Equality Act 2010, meaning that any retaliation by the employer for raising the grievance may itself constitute unlawful victimisation. Third, where the matter involves a potential whistleblowing disclosure: raising a formal grievance in writing helps document the protected disclosure and the employer's response.

A formal grievance letter for use in England and Wales should contain a number of key elements to trigger the statutory grievance process and protect the employee's legal position.

First, the letter must state clearly that it constitutes a formal grievance under the ACAS Code of Practice on Disciplinary and Grievance Procedures. This puts the employer on clear notice that the statutory Code applies and that the employer is expected to follow the full formal grievance procedure, including holding a grievance meeting and providing a right of appeal. A letter that merely expresses dissatisfaction — without expressly stating that it is a formal grievance — may not trigger the employer's obligations under the Code.

Second, the letter must set out the full details of the grievance clearly and factually. The description should include: the nature of the complaint (for example, bullying, discrimination, or breach of contract); the dates and circumstances in which the relevant events occurred; the names and roles of the individuals involved; any witnesses to the relevant events; and the effect the matters complained of have had on the employee. A clear, specific, and factual account is far more persuasive — both to the employer and to an Employment Tribunal — than a vague or emotional account.

Third, where applicable, the letter should identify the legal framework engaged by the grievance. For example, a grievance about harassment related to a protected characteristic should refer to the Equality Act 2010; a grievance about an unlawful deduction from wages should refer to Part II of the Employment Rights Act 1996; a grievance about a failure to make reasonable adjustments should refer to Section 20 of the Equality Act 2010.

Fourth, the letter should describe any informal steps already taken to resolve the matter, and explain why those steps were insufficient. This demonstrates that the employee has acted reasonably and has given the employer a prior opportunity to address the complaint.

Fifth, the letter should state clearly what outcome or remedy the employee is seeking. A specific request — for example, for a formal investigation, for the removal of the employee from the complainant's reporting line, or for a written apology — helps focus the employer's response and demonstrates the employee's constructive approach to resolution.

Finally, the letter should invoke the employee's statutory right to be accompanied at the grievance meeting by a trade union representative or work colleague, pursuant to Section 10 of the Employment Relations Act 1999, and request that sufficient notice of the meeting be given to allow the companion to attend.