Working in Two or More Member States: Article 13, the 25 % Rule and the A1 for Multi-State Workers

Regulations (EC) No 883/2004 and No 987/2009 have applied directly since 1 May 2010 in the EU and, through the EEA Agreement and the Agreement on the Free Movement of Persons, in Norway, Iceland, Liechtenstein and Switzerland; the United Kingdom applies Article SSC.12 of the EU-UK Protocol on Social Security Coordination. The Title II rules for posted workers in the EU also cover people working in several States at once.

The sections cover the definition, the applicable law, the 25 % indicator, the procedure, transport workers, the 2028 changes and a check.

Who Is a Multi-State Worker under Article 13?

A multi-state worker is a person who normally pursues an activity in two or more Member States, and for employed persons Article 13(1) of Regulation (EC) No 883/2004 sets the rule, with the details in Articles 14(5) to (11) and 16 of Regulation (EC) No 987/2009. Article 13 of Regulation (EC) No 883/2004 is a special rule beside the State-of-work rule of Article 11(3)(a) and posting under Article 12. Employed and self-employed activity in different States means the law of the State of the employed activity (Article 13(3)).

One State's legislation covers all of the person's activities, and the A1 shows which State that is. The wider Title II system explains which country's social security law applies to posted workers.

Habitual Work in Several States Versus Successive Assignments

Work in two or more States has to be the normal pattern, and the Court of Justice held in C-115/11 Format (4 October 2012) that successive contracts with work in one State at a time are not multi-state employment. The Format judgment interpreted Article 14(2)(b) of Regulation (EEC) No 1408/71, the predecessor rule.

The pattern is assessed on the situation projected for the following 12 calendar months (Article 14(10) of Regulation (EC) No 987/2009). A temporary assignment to one State is a posting question instead.

Which Country's Law Covers an Employed Multi-State Worker?

An employed person who normally works in two or more Member States is subject to the legislation of the State of residence if a substantial part of the activity is pursued there (Article 13(1)(a) of Regulation (EC) No 883/2004); if not, Article 13(1)(b) decides by the registered office or place of business of the employer. The table runs the four questions in order.

Article 13(1)(b) of Regulation (EC) No 883/2004 has four cases: (i) one employer: its registered office or place of business; (ii) several employers based in one State: that State; (iii) several employers based in two States, one being the State of residence: the other State; (iv) several employers, at least two based in different States other than the State of residence: the State of residence. Article 14(5a) of Regulation (EC) No 987/2009 places the registered office or place of business where the essential decisions are adopted and central administration is carried out.

Self-employed persons fall under Article 13(2) of Regulation (EC) No 883/2004 (State of residence if a substantial part is there, otherwise the centre of interest), covered under A1 for the self-employed working in several States.

The 25 % Substantial-Part Indicator of Article 14(8)

Under Article 14(8) of Regulation (EC) No 987/2009, a share of less than 25 % of working time and/or remuneration in the State of residence indicates that a substantial part of the activity is not pursued there. The consolidated Regulation (EC) No 987/2009 treats a substantial part as quantitatively substantial, not necessarily the major part, and the 25 % share as one indicator in an overall assessment, not an automatic result.

The table applies the indicator to three illustrative workers.

The figures are illustrative and calculated; worker C shows why the "and/or" matters. The Administrative Commission's Practical Guide on applicable legislation (December 2013), guidance and not law, says the legislation determined should in principle remain stable for the following 12 calendar months.

How the State of Residence Determines the Applicable Law

The person informs the designated institution of the Member State of residence, which determines provisionally which legislation applies, and that provisional determination becomes definitive after two months (Article 16(1) and (3) of Regulation (EC) No 987/2009). The A1 then shows the legislation determined.

Where institutions disagree, Article 6 of Regulation (EC) No 987/2009 gives provisional membership of one system; after one month the Administrative Commission can be asked, and it has six months to reconcile the positions. Disputes and withdrawal are covered under A1 validity and withdrawal.

Three national routes are listed below.

• Germany: the GKV-Spitzenverband, Deutsche Verbindungsstelle Krankenversicherung - Ausland (the DVKA) issues the A1 for multi-state activity of residents of Germany.
• United Kingdom: Article SSC.12 of the TCA Protocol, with the same less-than-25 % indicator (Article SSCI.13(11)) and a determination definitive within two months (Article SSCI.15(3)); HMRC form CA8421: HMRC A1 under the UK-EU Protocol.
• Every other State: see the competent institution in all 32 countries.

Contributions When the Employer Is Established Elsewhere

An employer that is not established in the competent Member State fulfils its social security contribution obligations as if it were established there (Article 21(1) of Regulation (EC) No 987/2009). Under Article 21(2), an employer without a place of business in the competent State may agree that the employee pays the contributions on its behalf; the employer remains responsible and notifies the competent institution.

International Lorry Drivers and Other Transport Workers

Drivers and other transport workers who normally work in two or more Member States fall under the same Article 13 rules as other employed persons, because Regulation (EC) No 883/2004 did not carry over the special transport rules of Regulation (EEC) No 1408/71, according to the Administrative Commission's Practical Guide on applicable legislation. Under those rules, a driver with one employer and less than 25 % of the work in the State of residence (Article 14(8) of Regulation (EC) No 987/2009) is covered by the State of the employer's registered office or place of business (Article 13(1)(b)(i)).

In C-610/18 AFMB (Grand Chamber, 16 July 2020), the Court of Justice held that, for Article 13(1)(b)(i) of Regulation (EC) No 883/2004, the employer of an international lorry driver is the undertaking with actual authority over him, which bears the wage costs and can dismiss him; the ruling is summarised with the other posting of workers case law.

What Changes for Multi-State Workers from 2 November 2028

Regulation (EU) 2026/2359 has been in force since 1 November 2026, but its changes to Article 13 of Regulation (EC) No 883/2004 and Articles 14 and 16 of Regulation (EC) No 987/2009 apply only from 2 November 2028; until then the rules described above apply unchanged. The table compares the text of Regulation (EU) 2026/2359 of 7 October 2026 with today's rules; article numbers refer to Regulation (EC) No 987/2009 unless Regulation (EC) No 883/2004 is named.

The amended paragraphs are Article 13(4a) and (5) of Regulation (EC) No 883/2004 and Articles 14(5a), (10), (12) and 16(1), (2), (3) and (5) of Regulation (EC) No 987/2009, not Article 14(8). The general Title II transitional period of Article 87b(4) of Regulation (EC) No 883/2004 as amended runs until 2 November 2036 and does not apply to Article 12. The take-over of Regulation (EU) 2026/2359 by Norway, Iceland, Liechtenstein and Switzerland is pending as of 5 November 2026.

How to Handle a Multi-State Work Pattern

Check a multi-state pattern before the work starts and again whenever the share of work in the State of residence changes.

Every other duty appears in the posting compliance checklist. The six steps under Regulation (EC) No 987/2009 are listed below.

1. List the States of normal work over the following 12 calendar months (Article 14(10)).
2. Compare the working time and remuneration share in the State of residence with 25 % (Article 14(8)).
3. Have the person inform the designated institution of the State of residence (Article 16(1)); from 2 November 2028 in the EU, the employer may do so.
4. Apply the provisional determination, definitive after two months (Article 16(3)).
5. Pay contributions under the legislation determined (Article 21(1)).
6. Recheck when the share of work changes; from 2 November 2028 in the EU, expect a reassessment after at most 24 months.

Only the designated institution of the State of residence makes the determination (Article 16 of Regulation (EC) No 987/2009).

Multi-State Work Beside Posting, Telework and Frontier Work

Article 13 is one of several rules on work across borders, and seven neighbouring situations follow other rules, each on its own page. The seven situations are listed below.

• Posting: Article 12(1) of Regulation (EC) No 883/2004, anticipated duration up to 24 months: the 24-month posting rule.
• Host-country pay: a labour-law clock, long-term posting after 12 months or 18 on a motivated notification (Article 3(1a) of the Posting of Workers Directive 96/71/EC).
• Telework: at least 25 % and less than 50 % in the State of residence, under the Framework Agreement on Article 16(1) of Regulation (EC) No 883/2004: cross-border telework under the Framework Agreement.
• Frontier workers: the State of work applies (Article 11(3)(a) of Regulation (EC) No 883/2004), Article 13 only if they also work in the State of residence: frontier workers and posted workers.
• Exception agreements: derogations agreed under Article 16(1) of Regulation (EC) No 883/2004: Article 16 exception agreements.
• Business trips: no EU exemption today; from 2 November 2028 exempt from prior notification (Article 15(1b) of Regulation (EC) No 987/2009 as amended), as are activities of up to three consecutive days within 30 consecutive days, except Annex 6 construction work: A1 for business trips.
• Drivers under labour law: Directive (EU) 2020/1057, applicable since 2 February 2022: posting of drivers.

The 12-month projection of Article 14(10) of Regulation (EC) No 987/2009 is separate from both clocks.

Multi-State Worker Questions

Four questions come up most often about multi-state work.

Does a multi-state worker need an A1?

The A1 shows which State's legislation applies; for work in two or more Member States it follows the determination of the State of residence's designated institution (Article 16 of Regulation (EC) No 987/2009). Under Article 19(2), the A1 certificate attests that legislation, until what date and under what conditions.

What happens when less than 25 % of the work is in the State of residence?

In the EU, the EEA and Switzerland, less than 25 % of working time and/or remuneration in the State of residence indicates no substantial part there (Article 14(8) of Regulation (EC) No 987/2009); with one employer, the State of its registered office or place of business then applies (Article 13(1)(b) of Regulation (EC) No 883/2004).

Who decides which country's law applies to a multi-state worker?

The designated institution of the State of residence decides provisionally, and its determination becomes definitive after two months (Article 16(3) of Regulation (EC) No 987/2009). In the EU from 2 November 2028, the employer may also notify it on the person's behalf.

Does the 2026 revision change the 25 % rule?

No: Regulation (EU) 2026/2359 does not amend Article 14(8) of Regulation (EC) No 987/2009. From 2 November 2028 in the EU, a multi-state determination lasts at most 24 months before reassessment; the take-over by Norway, Iceland, Liechtenstein and Switzerland is pending as of 5 November 2026.