PUBLISHED ON 24/10/2023

Welcome to the Brexit Brief! In this newsletter for UK citizens living in Brussels or thinking of moving here, we will explore some of the more complicated aspects of life after Brexit. Each edition will start from a puzzling everyday question, using it as a chance to explore the rules that UK citizens should know about.

Case Study 8: “I am a UK citizen living in the UK. My spouse has moved to Belgium to work on a local contract with a Belgian employer. I will be moving to Belgium with them, as will our two children (both under 18). I have already worked in the UK for 5 years, and will continue to work for my UK employer – sometimes remotely from our home in Belgium and sometimes travelling back to the UK office. What does this all mean for me and my family in terms of social security, including pensions and child benefits?”

This month’s Brexit Brief is a follow-up to the previous edition about income tax for cross-border workers and families. We will not be explaining the intricacies of government budgets, but it is important to begin with a reminder that both the UK and Belgium distinguish between general income taxation and a social security/national insurance system funded by specific levies. Social security/national insurance contributions give the payee (and their family) entitlement to certain forms of social security benefits. This edition of the Brexit Brief therefore focuses not only on where you should pay those contributions, but also on where and how you can access some of the benefits they entitle you to.

We will approach the issue through four questions.

  1. Where should I pay social security contributions?
  2. Where can I access immediate individual-level social security (unemployment coverage and healthcare)?
  3. Where can I access family-level social security (child benefits)?
  4. Where can I access social security rights accrued across my career (pensions)?

Across these questions, we will explore the various impacts of different constellations for workers or families who move to Belgium, using practical cases like the one above to guide the discussion.

1. Where should I pay social security contributions?

In the case study mentioned in the beginning of this newsletter, the spouse is already working in Belgium on a Belgian employment contract. That situation is simple: the spouse is subject to Belgian social security contributions (cotisations sociales / sociale zekerheidsbijdragen). These contributions will be retained and transferred to the state by their employer.

For the UK citizen moving to Belgium to join their spouse while continuing to work for a UK employer, the situation is a little more complex. The post-Brexit Trade and Cooperation Agreement (TCA) between the UK and the EU will only allow you to remain subject to one social security system. You will therefore (continue to) pay social contributions only in one country at any given time. But which one?

In principle, you will be subject to the social security system of the country where you work, not simply where the contract is signed or the employer is based. However, if you live in Belgium and sometimes work remotely for a UK employer, the days worked in Belgium would count as days worked in Belgium, while the days worked in UK would count as days worked in UK. This would go against the principle that you can be subject to only one social security system, so there is a clarification for these situations in the TCA.

In general, if you are working 2 days per week from Belgium, you are deemed to perform a substantial part of your employment in Belgium, the country where you live. You therefore have to pay social contributions in Belgium on all of your employment income. Your UK employer will have to affiliate you to the Belgian system and pay Belgian contributions accordingly. For the days that you still work in the UK, you will not be expected to make national insurance contributions in the UK. Your UK employer will be able to request a certificate of social security coverage in Belgium, called an A1 certificate, to show the UK authorities that you are indeed correctly paying social security contributions in Belgium. The certificate issued in Belgium will normally be issued for 12 months, but is renewable as long as the mentioned employment arrangement lasts.

On the contrary, if you work less than 25% of your total working time from Belgium, then you might remain exclusively subject to UK national insurance contributions. Also in this situation, you will have to obtain an A1 certificate, this time from the UK authorities, showing that you remain subject to UK social security for all your work duties (both in Belgium and in UK). This will protect you in case the Belgian authorities ask you for any clarification. This A1 form will cover you also in other EU countries, should you visit these for work during the period of validity of the certificate.

2. Where can I access healthcare and unemployment benefits?

The individual level of social security coverage mainly consists of healthcare and unemployment benefits. In principle, you will be covered by the system of the country where you pay the contributions.

To access unemployment benefits if you lose your job, you would apply in the country of coverage. If deemed eligible, you would then receive the payments established by that system. If you are out of work for an extended period, be aware that this might have an impact on your right of residence in Belgium. You should seek advice rapidly after losing your job.

When it comes to healthcare, a Belgian resident mainly working here and paying social security contributions here should register with a health insurance fund (mutuelle /ziekenfonds). If you get ill while in the UK, your EHIC issued by your health insurance fund will give you access to the necessary healthcare. Likewise, if you are mainly based in the UK but work one day per week in Belgium, you will be able to access necessary healthcare here in the same way as a tourist does (using a GHIC). Benefits for long-term sickness and disability are paid by the country where you are covered.

3. Are we entitled to child benefits, and where?

If you are covered under the Belgian social security system and you are working as an employee in Belgium, even for a UK employer, you may register with a family benefits fund (caisse d'allocations familiales / kinderbijslagfonds). You are then, in principle, entitled to receive monthly family allowance payments for eligible children in your household, dependent on their age and status. Child benefits are managed by the regions in Belgium and not by the federal social security system, therefore each region has its own policies and procedures.

Note that if you moved to Belgium before the end of the Brexit transition period on 31 December 2020 and your dependent children continued to live in the UK, you might still be entitled to family benefits “as if” they were living in Belgium. This is no longer the case if you moved to Belgium as from January 2021, once the Brexit transition period had ended.

If your work arrangements mean that you are still covered by the UK social security system, then you would not be entitled to apply for Belgian family allowances, even if your children live in Belgium. However, according to the case study at the beginning of this article, your spouse is covered by the Belgian social security system. In that case, your spouse might therefore have an autonomous right to family allowances.

4. Where will we get our state pensions in the end?

If your spouse works exclusively in Belgium, they will be subject to Belgian social security contributions and will start accumulating state pension rights in Belgium. Likewise, if your work arrangement with your UK employer means that you are subject to Belgian social security contributions, you will also start building up pension rights in Belgium. On the contrary, if you continue to be subject to UK national insurance, you will continue to accumulate pension rights in UK and not in Belgium. In any case, considering the example at the beginning of the article, it is likely that one or both of you will find yourselves with a “mixed pot” of state pension contributions in the UK and Belgium systems.

If you have accumulated entitlements in Belgium, you will be able to submit a Belgian pension application when you meet the Belgian legal pension requirements (notably in terms of age). You may do this in Belgium. However, the social security regulations in place after Brexit mean that individuals retiring in the UK can also apply for their Belgian pension through the UK pension authority. Just inform the UK authorities that you have worked in Belgium during your career. Likewise, if you retire in Belgium, make sure to inform the authorities that you have worked and paid national insurance in the UK. The country where you retire does not affect your UK or Belgian state pension rights, and you can receive payments from both systems paid out by both pension authorities.

In the UK, there is a minimum contributing period in order to access a state pension entitlement. It can be difficult to achieve this minimum if you move very early/late in your career, or if you spend many years outside the labour market. However, if your social insurance periods in one country are not sufficient to give you access to a pension benefit, the competent authorities will totalise the periods accrued in Belgium and the UK in order to assess your right to access a pension. This means that any contributions you “left behind” in the UK will not be lost, and you should be able to get some state pension in both the UK and Belgium. Once the amount of your Belgian state pension is calculated by the authorities, this will be perfectly exportable to UK (and vice versa).

The amount of your pension benefits in Belgium or the UK respectively will be calculated based upon the actual working periods for which you paid contributions in each country. Thanks to the totalising principle, you will not lose pension entitlements for contributing years in either country, but nor will you be paid twice by receiving pension payments from one country for time you worked in the other.


Welcome to the Brexit Brief! In this newsletter for UK citizens living in Brussels or thinking of moving here, we explore some of the more complicated aspects of life after Brexit. Each edition starts from a puzzling everyday question, using it as a chance to present the rules that UK citizens should know about. Some newsletters are relevant for M-Card holders, some for those arriving after Brexit, and some for all UK citizens. This newsletter is part of a project funded by the EU’s Brexit Adjustment Reserve, in which we are also developing a series of webinars and an online Brexit HelpdeskTo receive this monthly newsletter straight to your inbox, sign up today!


These pages, webinars and newsletters have been developed in a project funded by the EU’s Brexit Adjustment Reserve.

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