Salary Increment Letter (UK)

A Salary Increment Letter in the United Kingdom is a legally binding written instrument.

In UK employment law, salary is one of the core terms of the employment contract. Under section 1(4) of the Employment Rights Act 1996, the scale or rate of remuneration, or the method of calculating remuneration, must be included in the written statement of employment particulars. Any change to this term — including an increase in salary — constitutes a variation of the employment contract. While employees rarely object to a salary increase, best practice (and in some cases legal requirement) is to confirm the new terms in writing.

The need for a written record of salary changes is reinforced by HMRC's requirements. Employers are required to update the employee's payroll record when their salary changes and to operate PAYE correctly on the new salary from the effective date. Maintaining a clear paper trail of salary changes — starting with the salary increment letter — makes it easier to reconcile payroll records, respond to HMRC enquiries, and resolve any disputes about the correct salary at a later date.

Salary increment letters are also important in the context of the National Minimum Wage Act 1998. All employees must be paid at least the applicable National Minimum Wage rate (the National Living Wage for those aged 21 and over, currently £11.44 per hour from April 2024). Failing to increase a salary to keep pace with the annual increases to the National Living Wage is a breach of the Act and can result in civil penalties of up to 200% of the underpayment and public 'naming and shaming' by HMRC. Issuing salary increment letters as part of the annual pay review process, and confirming that all employees remain above the statutory minimums, is therefore an important compliance function.

From an employee relations perspective, a well-drafted salary increment letter is a positive tool for engagement and retention. It formally recognises the employee's contribution, communicates the employer's valuation of their service, and provides the employee with a document they can use for personal financial planning, mortgage applications, and other purposes. Many financial institutions require a salary increment letter as evidence of increased earnings when an employee is re-mortgaging or applying for a new loan.

The letter should also address whether the salary increase is consolidated into the base salary (i.e. becomes the new contractual salary going forward) or whether it is a one-off payment (a non-consolidated award or bonus). Consolidated increases are the most common form of annual pay review and become the new contractual salary from the effective date. Non-consolidated awards are a separate matter and should be documented as such.

A salary increment letter should be issued every time an employee's base salary is increased, regardless of the reason for the increase. The most common occasions are the annual pay review (typically timed to coincide with the start of the financial year or the beginning of the calendar year), a promotion to a more senior role, exceptional performance recognition outside the annual review cycle, and the mandatory increase to comply with increases to the National Living Wage or National Minimum Wage.

For the annual pay review, the salary increment letter should be issued promptly after the pay review decisions have been made and communicated to employees. Delay between the decision being made and the letter being issued creates uncertainty and can damage employee relations. Many organisations aim to issue salary increment letters within two weeks of the annual review meeting.

For promotions, the salary increment letter or a new offer letter should be issued before the promotion takes effect. A verbal agreement to increase the salary is not sufficient — under employment law, a variation of contract is only legally effective when both parties have agreed to it, and written confirmation of the agreement provides the clearest evidence of this.

For National Minimum Wage increases, the salary increment letter confirms to the employee that their pay has been updated to comply with the new legal minimum. Employers should review all salaries whenever the National Living Wage or National Minimum Wage rates increase (typically in April each year) and issue increment letters to all employees whose salaries have been increased as a result.

The letter should be retained in the employee's personnel file as a permanent record of the salary history. This record is useful for calculating redundancy pay (which is based on a week's pay, which in turn depends on the employee's contractual salary), for calculating notice pay, and for responding to subject access requests under the UK GDPR.

Under the Employment Rights Act 1996, the Employment Tribunal adjudicates workplace disputes. Section 94 of the Employment Rights Act 1996 provides the right not to be unfairly dismissed. The Advisory, Conciliation and Arbitration Service (ACAS) provides early conciliation under Section 18A of the Employment Tribunals Act 1996. The UK GDPR and Data Protection Act 2018 govern personal data handling. HM Revenue and Customs (HMRC) administers PAYE and National Insurance contributions under the Income Tax (Earnings and Pensions) Act 2003.

A UK salary increment letter should contain the following essential elements.

The opening should identify the employer (company name and address) and address the letter personally to the employee by their full name and current job title. It should be dated clearly.

The pay review section should state the employee's current (pre-increase) annual gross salary and the new annual gross salary, expressed as a figure in pounds sterling. It should also state the percentage increase, both as a management communication tool and as a record for payroll purposes.

The effective date is critical. The letter must state clearly the date from which the new salary takes effect. This is the date from which PAYE must be operated on the new salary, and it determines the point at which the employee is entitled to receive the higher pay. If the pay review is backdated to a date before the letter is issued (which is common in annual reviews where decisions are made after the intended effective date), the amount of backdated pay should be calculated and stated in the letter.

If the increase is linked to performance, the letter may acknowledge the employee's performance or contribution in general terms. However, the letter should not make commitments about future pay reviews or create an expectation of further increases — these can create legal complications if the employer's financial position changes.

If the increase is conditional on anything — for example, on the employee remaining in employment until a specified date, or on the completion of a satisfactory probation period — this condition should be stated clearly.

The letter should confirm whether any other terms of employment remain unchanged. A statement such as 'all other terms and conditions of your employment remain unchanged' provides useful clarity and avoids any argument that the letter varied other terms as well as the salary.

The letter should invite the employee to confirm their acceptance by signing and returning a copy. Since the increase is universally welcomed, this step is often omitted in practice, but it provides the best legal protection for the employer and creates the clearest record of the agreed variation.

Additional compliance elements for a Salary Increment Letter (UK) used in United Kingdom include: Under the Employment Rights Act 1996, the Employment Tribunal adjudicates workplace disputes. Section 94 of the Employment Rights Act 1996 provides the right not to be unfairly dismissed. The Advisory, Conciliation and Arbitration Service (ACAS) provides early conciliation under Section 18A of the Employment Tribunals Act 1996. The UK GDPR and Data Protection Act 2018 govern personal data handling. HM Revenue and Customs (HMRC) administers PAYE and National Insurance contributions under the Income Tax (Earnings and Pensions) Act 2003. Forms-legal.com provides this template as a starting point for United Kingdom-compliant documentation.