National Insurance in the UK

The National Insurance in the UK is what is also known as Social Security. Workers over 16 residing in the UK must contribute to national insurance to access all benefits.

However, EU workers temporarily posted to UK may not have the same obligations as UK residents.

National Insurance in the UK

The Department for Work and Pensions (DWP) oversees social security in the UK, having replaced the Department of Social Security in 2001. It has the highest spending among all government departments and is responsible for delivering the State Pension along with various benefits for working-age individuals.

In addition to the above-mentioned department, His Majesty’s Revenue and Customs (HMRC) administers National Insurance contributions and Child Benefit. The National Insurance Scheme is the contributory part of the UK social security system, and a National Insurance Number (NIN) identifies an individual’s tax and contribution records; it is not restricted to British citizens.

Workers in the United Kingdom who have their own NIN may pay different types of contributions, known as classes, based on their employment conditions. As a basic principle, individuals aged 16 or over who are subject to UK social security legislation should pay National Insurance contributions if they:

• are employees earning more than £242 a week; or
• are self-employed workers with annual profits exceeding £12,570.

National Insurance Classes and Categories in the UK

The UK divides National Insurance into classes based on employment status and earnings. Workers and employers pay contributions under the applicable classes, which are:

• Class 1: all the employees earning more than £242 a week and under State Pension age. 
• Class 1A or 1B: employers pay these on certain employees’ expenses and benefits.
• Class 2: self-employed workers. In 2026/27, Class 2 contributions are no longer compulsory: if profits are above the small profits threshold (£7,105 a year) they are treated as paid; below that threshold, self-employed workers may pay voluntary Class 2 contributions (£3.65 a week) to protect their entitlement to benefits and State Pension.
• Class 3: voluntary contributions that eligible individuals may pay to fill gaps in their National Insurance record, which may arise from low earnings, previous unemployment, or periods spent living or working outside the UK.
• Class 4: self-employed workers with annual profits above £12,570: 6% on profits between £12,570 and £50,270, and 2% on profits above £50,270.

Employers also pay Class 1 National Insurance contributions on employees’ earnings. For most employees, the employer rate is 15% on earnings above the Secondary Threshold, currently £96 a week in 2026/27. Different rates or thresholds may apply in specific cases.

To assess how much employees or employers need to contribute, employers use National Insurance category letters when running payroll. These include A, B, C, D, E, F, H, I, J, K, L, M, N, S, V and Z. Most workers belong to category letter A. Letter X is used for employees who do not have to pay National Insurance, such as those under 16.

Every year in April HM Revenue and Customs (HMRC) publishes the applicable contribution thresholds and rates for each tax year.

How to apply for a NIN in the UK

To be eligible to apply for a NIN in the UK, the applicant must:

• Live in the UK,
• Have the right to work in the UK,
• Be working, looking for work or have an offer to start work.

To start the online application, the applicant must have either one of these documents:

• A passport,
• A national identity card issued by an EU country, Norway, Liechtenstein or Switzerland.

Once applicants complete the procedure, the competent authorities will review it and issue the National Insurance Number if the application is successful. It can take up to four weeks to receive the number after the applicant has proved their identity.

You must apply online for a National Insurance number. If you cannot upload photos of your documents, you can still apply online, but your application may take longer. You may be asked to attend an appointment or post photocopies of your documents.

Foreign Workers in the UK

Workers coming to the UK from an EU Country will usually pay for only one social contribution scheme, thanks to the social agreements with those Countries.

In this regards, the employer or self-employed worker must apply for the A1Certificate from the competent social security institution in the country where the work is performed. (EU Regulation 883/04).

Said certificate can be requested for employees working temporarily in the UK for up to 2 years.

Although the legal basis of the Eu Regulation is not valid anymore in the UK, it still holds its validity thanks to the PSSC (Protocol on Social Security Regulation), which entered into force with the conclusion of the EU-UK TCA.

Workers coming from Iceland, Liechtenstein, Norway or Switzerland should check which social security agreement applies to their circumstances. The applicable agreement determines where contributions are due and which certificate of coverage is required.

If the worker is not covered by any social security agreement, UK domestic rules determine whether National Insurance contributions are payable.

However, the worker can avoid paying National Insurance for the first 52 week of working in UK if he meets all the following requirements:

• the worker is not ordinarily resident in the UK;
• the worker normally works outside the UK for a non-UK employer;
• the foreign employer sends the worker to work in the UK for a limited time (temporary secondment);
• and while in the UK, the worker continues to work for that same foreign employer.