Payroll Calculation UK: HMRC & RTI Compliance Guide 2025
Accurate payroll calculation is a legal requirement under HMRC's Real Time Information (RTI) regime. Every UK employer must report payments and deductions on or before each payday. Mistakes can trigger penalties under the PAYE Settlement Agreement rules. This guide walks you through the essential steps and statutory obligations for 2025, including National Insurance contributions and pension auto-enrolment.
1. Legal Framework & RTI Reporting
In the UK, payroll must comply with the Income Tax (Pay As You Earn) Regulations 2003 and the National Insurance Contributions Act. Since 2013, HMRC requires RTI (Real Time Information) – you must submit a Full Payment Submission (FPS) on or before each payday, not after. Late submissions can incur penalties starting at £100 per month. Also, you must register as an employer with HMRC (usually before the first payday) and provide payslips to all staff under the Employment Rights Act 1996. Failure to report accurately may trigger an employer compliance check.
2. Calculating PAYE and NIC
For the 2025/26 tax year, most employees have a standard Personal Allowance of £12,570. Use HMRC's tax tables (often integrated into payroll software) to deduct PAYE via the cumulative code (e.g., 1257L). National Insurance Contributions (NIC) are calculated on earnings above the Primary Threshold (£242 per week in 2025/26) at 8% for employees, plus 2% above the Upper Earnings Limit (£967 per week). Employers also pay Class 1 NIC at 13.8% on earnings above the Secondary Threshold (£175 per week). Always verify thresholds against HMRC's latest rates, as they change annually.
3. Statutory Payments and Student Loans
Payroll must include Statutory Sick Pay (SSP) for eligible employees earning at least £123 per week (2025/26). Also, Statutory Maternity, Paternity, and Adoption Pay are due after qualifying service, with rates set by the government. If the employee has a student loan or postgraduate loan plan (e.g., Plan 1, 2, 4, or 5), you must deduct repayments once their earnings exceed the threshold (e.g., £2,082 per month for Plan 1). Check the employee's starter checklist (HMRC form) to apply the correct code. Incorrect deductions can lead to underpayment and HMRC interest charges.
4. Pension Auto-Enrolment and Reporting
Under the Pensions Act 2008, you must automatically enrol eligible workers (aged 22 to state pension age, earning over £10,000) into a qualifying workplace pension. The minimum contribution is 8% of qualifying earnings (with at least 3% from employer) – but many schemes use different bases. You must calculate and deduct employee contributions via payroll and report them on the FPS. Also, complete a Pension Regulator declaration of compliance within 5 months of the staging date. Failing to auto-enrol can result in fines from The Pensions Regulator. Use a certified pension provider to integrate with payroll.
Cómo te ayuda OficioIA
HandymenAI can assist finance professionals by automating payroll calculations, checking HMRC thresholds, and flagging potential RTI errors before submission. It also provides up-to-date guidance on regulatory changes like NIC rates and pension contributions, saving time and reducing compliance risk.
Get Expert Help from HandymenAIPreguntas frecuentes
What is the deadline for RTI submissions in the UK?
Under HMRC's Real Time Information, you must send the Full Payment Submission (FPS) to HMRC on or before each payday – not after. There is no monthly or quarterly summary; each pay run is reported in real time. Late submissions can incur penalties.
How do I calculate National Insurance contributions for employees?
For the 2025/26 tax year, employees pay Class 1 NIC at 8% on earnings between £242 and £967 per week, and 2% above that. Employers pay 13.8% on earnings above £175 per week. Always use HMRC's latest rates and thresholds, as they change annually each April.
What are the pension auto-enrolment minimum contributions?
The minimum total contribution is 8% of qualifying earnings, with at least 3% coming from the employer. For example, if an employee earns £30,000, the minimum contribution is £2,400 per year, where the employer pays at least £900. You must deduct the employee's share via payroll and report it on your FPS.
finanzas/agente_finanzas
¿Necesitás aplicar esto en tu trabajo?
El finanzas/agente_finanzas de OficioIA te guía paso a paso con normativa actualizada de tu país, documentos a medida y respuestas en segundos.
Get Expert Help from HandymenAI →14 días gratis · Sin tarjeta de crédito