National Insurance Certificate for Self-Employed Working Abroad

If you're self-employed and planning to work temporarily in an EU country or certain other European nations, you may need a certificate (form CA3837) confirming you'll continue paying UK National Insurance. This certificate proves to foreign authorities that you remain in the UK social security system, and can also give you access to UK-funded healthcare in your country of residence.

Who needs this certificate

You should apply for a CA3837 certificate if you're a self-employed individual planning to work temporarily in:

• Any EU country
• Gibraltar
• Iceland
• Liechtenstein
• Norway
• Switzerland

The certificate is also required if you'll be carrying out self-employed work on a ship or vessel flying the flag of any of these countries.

If you're unsure whether this is the right form for your circumstances, HMRC provides an interactive guidance tool to help you check which application form you need.

When to apply

You cannot apply more than 12 months in advance of your planned work abroad. This means you should plan your application timing carefully, giving HMRC enough time to process your request but not submitting it too early.

Information you'll need to provide

When completing the CA3837 form, you must have several pieces of information ready.

Basic personal details:

• Your country and place of birth
• Your name and any previous names
• All nationalities you hold
• The address of your self-employed business
• The type of work you carry out in the UK and what you'll do abroad

Maintaining your UK business:

You'll need to explain whether you're maintaining your UK self-employment whilst working abroad. This includes details about:

• Keeping your UK business office
• Keeping your equipment
• Maintaining your business registration
• Continuing to advertise your UK business

Additional details may be required if:

You have a spouse or partner with EU Settlement Scheme status, or you hold a non-UK nationality acquired before 1 January 2021. You'll also need information about your right to work in the UK (including what type and whether you held it before 1 January 2021).

If you have a current right to reside in an EU country, Gibraltar, Iceland, Liechtenstein, Norway or Switzerland, you must know whether you held this right before 1 January 2021.

You'll need to provide the start date of your UK self-employment if you've been self-employed in the UK for less than 2 months before your start date abroad. If you work on a continental shelf area, this information is also required.

If you work onboard a vessel at sea, you must know which country's flag is flown on the vessel.

Healthcare entitlement

If you'll be resident (not just working temporarily) in an EU country, Iceland, Liechtenstein, Norway or Switzerland, you may be entitled to healthcare funded by the UK in your country of residence.

When HMRC processes your application, they'll consider whether you qualify for UK-funded healthcare. If you do qualify, HMRC will issue you with a healthcare entitlement certificate (also known as an S1 certificate) alongside your National Insurance certificate.

Dependants:

If you have dependants living with you who need healthcare cover, you must provide the following details for each dependant:

• Name
• Date of birth
• Their working status (if they are over 16 years old)

Applying for an extension

If you already have a certificate and need to extend your period abroad, you can apply for an extension using the same CA3837 form.

You'll need to provide:

• The date your existing certificate expires
• Details of any changes in your circumstances since your previous application

If the combined time period of your existing certificate and the extension is longer than normally allowed, you must attach a signed statement. This statement should explain why you want to continue paying UK National Insurance while working abroad and how it's in your best interest. This requirement only applies if you're covered by certain agreements.

How to apply

Applications are submitted online through HMRC's digital service. You'll need to sign in to use the service, and if you don't already have sign-in details, you can create them during the application process.

When you sign in, you may be told you need to prove your identity to keep your details safe. This normally involves using photo identification such as a passport or driving licence.

You don't have to complete the form in one sitting. You can save your answers and return to finish it later.

If you're using an agent

If an accountant or agent is applying on your behalf, you must first complete an authorising your agent form (64-8). This completed form should be submitted alongside the CA3837 application.

Processing times

After submitting your application, you can check when to expect a reply from HMRC using their online guidance on response times for different types of applications.

Sources

• Apply for a certificate to confirm you will pay UK National Insurance while self-employed abroad temporarily (CA3837)

This article provides general guidance based on current HMRC rules. For advice specific to your situation, speak to your accountant.