Brexit: Ireland/UK social security convention

Although the UK left the European Union on 31 January 2020, all existing EU social security co-ordination rules will continue to apply to the UK until the end of the transition period on 31 December 2020. In the context of employee mobility, these include rules on the country in which an employee is required to pay social security contributions, if they work outside their home country.

From 1 January 2021, if the transition period ends without any further agreement between the UK and the EU (a “hard Brexit”), the EU social security coordination rules will no longer apply to cross-border arrangements between UK employers and employees, including situations where an employee of an Irish employer spends time working in the UK. Instead, the rules in the UK and the country in which the employee works or has been seconded to will determine the social security position on a country by country basis.

A new convention on social security matters was signed by Ireland and the United Kingdom on 1 February 2019. The convention will preserve the social security arrangements currently in place under EU law relating to social security contributions, pensions and benefits, following the United Kingdom’s pending departure from the EU. When ratified by both countries, it will operate in conjunction with the existing 2007 convention which applies to persons moving between the Channel Islands, the Isle of Man and Ireland.

Key points

The convention ensures that lrish and UK nationals residing and/or working in the UK or Ireland do not lose their accrued rights to social security benefits when moving between the two countries. This means that the rights of Irish citizens living in Ireland to benefit from social insurance contributions made when working in the UK will be protected and vice versa. 

In addition, the convention provides rules to ensure that employees who work between the two countries are not liable to double social security contributions at the same time. For example, employees who are assigned from one country to the UK or vice versa to perform work for a period not exceeding 24 months shall remain insurable in their home country system, which mirrors existing EU rules. There are also provisions concerning the country of insurability of employees who spend time working between the two countries. 

What should employers consider?

Employers with operations between Ireland and the UK should review the validity of A1 documents obtained under EU social security rules for its mobile employees. The A1 documents confirm whether the employees should pay UK NIC or Irish PRSI on their employment income, however, following Brexit, it is unclear whether the A1s will cease to have effect immediately or whether they will continue to apply for a further transitionary period. In any event, employers will need to review the social security position of its mobile employees under the convention and take the appropriate steps to obtain confirmation of their country of insurability from the UK and Ireland security authorities.

If you have any questions in relation to the above, or if you would like to discuss this topic further, please contact a member of the Mazars employment tax team below:





Ken Killoran

Tax Partner

01 4494451

John Kelly

Tax Director

01 4494495

November 2020