Defer Paying Class 1 National Insurance on a Second Job

Employees with more than one job who want to understand why National Insurance deductions may differ across employments and whether deferment may apply. Explaining how Class 1 National Insurance works when you have a second job, why overpayments can occur, and how deferment operates in practice. Where an individual has more than one employment, National Insurance is normally calculated separately for each job. This can result in higher overall National Insurance deductions than necessary unless deferment applies. Understanding the rules helps avoid unnecessary overpayment and later adjustments.

When You Can Pay Reduced NIC Across More Than One Job

If you have 2 jobs, over the tax year you’ll need to earn:
  • £967 or more per week from one job over the tax year.
  • £242 or more per week in your second job
If you have more than 2 jobs, over the tax year you’ll need to earn:
  • £1,209 or more per week from 2 of those jobs
  • £242 or more per week in your other jobs
This deferral could result in NIC deductions at a reduced rate of 2% on your weekly earnings between £242 and £967 in one of your jobs, instead of the standard rate of 8%. If you are allowed to defer, HMRC will inform you which employer is your main one for full Class 1 National Insurance contributions and which employers you can pay at the reduced 2% rate, sending those employers a certificate of deferment. HMRC does not share information about your other jobs with your employers.

Class 1 National Insurance and Multiple Jobs

Class 1 National Insurance contributions apply to employment income and are deducted through PAYE. When you have more than one job, each employer must calculate National Insurance independently, without reference to earnings from your other employment. This means that total National Insurance paid across all jobs can exceed what would normally be due based on overall earnings.

Why National Insurance Can Be Overpaid

Overpayment can arise because:
  • Each job applies National Insurance thresholds separately
  • Earnings from multiple employments are not combined during the tax year
  • PAYE does not automatically account for total income across jobs
This is a common issue for individuals with a second job or multiple employments.

Deferring Class 1 National Insurance

Where total earnings are high enough, it may be possible to apply to defer paying Class 1 National Insurance on a second job. Key points include:
  • Deferment is not automatic
  • An application must be made to HMRC
  • HMRC must approve the deferment
Deferment changes how National Insurance is collected during the tax year. It does not remove the liability entirely.

How Deferment Works in Practice

In practice:
  • Employees may notice lower National Insurance deductions on a second job once deferment is applied
  • Employers must operate payroll in line with HMRC deferment instructions
  • National Insurance is reviewed as part of the year-end reconciliation
Any remaining National Insurance due is dealt with after the end of the tax year.

Risks and Consequences

If deferment is not applied for where eligible:
  • National Insurance may be overpaid during the year
  • Adjustments may be required following HMRC review
  • Refunds or corrections may only be processed after the tax year ends
These are administrative consequences rather than penalties, but they can affect cash flow.

When to Seek Advice

Deferment is not relevant in all cases. Advice may be helpful where:
    • You have more than one job, and deductions appear unusually high
    • There is uncertainty over whether deferment applies
    • Payroll treatment following HMRC approval is unclear

Need Help Applying for National Insurance Deferral?

Holding more than one job can lead to paying more National Insurance than necessary if contributions are not deferred correctly, and many people only realise this after deductions have already been made. Cigma Accounting helps individuals across London understand when deferral applies, how to apply properly, and how to avoid mistakes that can affect take-home pay or HMRC records, with clear guidance from an experienced tax accountant in London.

From our Kingston Upon Thames, supporting clients in Surbiton and Norbiton, we review second-job National Insurance in the context of your full income picture, not just one employer in isolation. With physical offices across London, our team can also help ensure payroll is set up correctly and aligned with HMRC requirements, providing dependable support through trusted accounting services London expertise.

PAYING TOO MUCH NATIONAL INSURANCE ACROSS MULTIPLE JOBS?

Holding more than one job can lead to higher Class 1 National Insurance deductions than necessary if deferral rules aren’t applied correctly. Clear advice can help you understand eligibility, avoid overpayments, and ensure HMRC deductions are handled properly.

Trusted guidance from London-based accountants, focused on accuracy, clarity, and compliance. 


author avatar
Aitch
Aitch is the visionary founder and CEO of CIGMA Accounting Ltd, a boutique accounting and tax advisory firm with offices in Wimbledon and Farringdon, London. With over a decade of experience, Aitch has built a reputation for strategic tax planning, complex HMRC compliance resolution, and innovative AI-powered accounting workflows that help SMEs, landlords, and high-net-worth clients streamline their finances. His expertise spans corporation tax, inheritance tax planning, R&D tax credit claims, capital allowances, and international tax matters, making him a trusted advisor for clients seeking to minimise tax liabilities while staying fully compliant. Aitch is passionate about bridging traditional accounting principles with cutting-edge digital solutions, allowing businesses to operate efficiently and future-proof their financial systems. Through CIGMA, he aims to make accounting smarter, faster, and more human-centric - empowering clients to focus on growth while staying ahead of regulatory changes.