Tax codes for employees

Employees, employers, payroll teams, and anyone paying tax through PAYE.

Explains how employee tax codes are structured, how they are applied through payroll, and how they affect Income Tax deductions.

An incorrect tax code can lead to overpaying or underpaying tax. Understanding how tax codes work helps identify issues early and avoid unexpected adjustments.

An employee’s tax code is used by HMRC to tell an employer or pension provider how much Income Tax to deduct under the Pay As You Earn (PAYE) system.

The tax code reflects the individual’s tax-free allowances and any adjustments required to collect tax owed or account for benefits.

How tax codes are structured

Most tax codes are made up of numbers and letters.

• The numbers generally indicate the amount of tax-free income an employee is entitled to in the tax year.
• The letters provide additional information about the individual’s tax situation.

For example, a code such as 1257L is commonly used where the standard Personal Allowance applies.

Common employee tax codes

Some commonly used tax codes include:

• L – Entitled to the standard Personal Allowance.
• BR – All income from this employment is taxed at the basic rate.
• D0 – All income from this employment is taxed at the higher rate.
• D1 – All income from this employment is taxed at the additional rate.
• K – Deductions exceed allowances, meaning additional tax is collected through PAYE.

How payroll applies tax codes

Employers apply the tax code provided by HMRC when running payroll.

The code determines how much tax is deducted from each payslip. If HMRC updates a tax code during the year, payroll must apply the revised code from the effective date shown.

Why an employee’s tax code may change

Tax codes can change due to:

• Changes in income.
• Starting or leaving employment.
• Benefits in kind being added or removed.
• HMRC adjusting the code to collect tax owed from earlier years.

Employees are normally notified when HMRC issues a new tax code.

Real-world impact

A change in tax code directly affects take-home pay. If a tax code reduces available allowances, more tax will be deducted each pay period. If allowances increase, take-home pay may rise.

Regularly reviewing payslips and tax code notices helps ensure deductions reflect actual circumstances.

Risks and consequences

If a tax code is incorrect and goes unnoticed, the error may continue across multiple pay periods.

This can result in overpaid tax or underpaid tax, which may later need to be corrected.

Next steps

If you are unsure whether your employee tax code is correct, checking it against your current circumstances can help prevent future adjustments.

Helping Employees Understand and Correct PAYE Tax Codes

Employee tax codes directly affect how much tax is deducted through PAYE, and even small coding mistakes can lead to significant underpayments or unexpected refunds. Cigma Accounting, operating from Farringdon in London, helps employees review their coding notices and understand HMRC adjustments, providing clarity and corrective support through an experienced tax accountant London focused on PAYE accuracy.

Where multiple employments, benefits, or prior year balances are involved, tax codes can quickly become difficult to interpret without specialist input. Individuals working around Holborn and Clerkenwell often need reassurance that their deductions are correct, and with physical offices across London, Cigma Accounting delivers practical guidance and reliable accounting services London when tax codes do not reflect your real circumstances.