Traditionally, the second day of the European Labour Mobility Congress opened with a Q&A session with experts from the Polish Social Insurance Institution (ZUS) — one of the most practical and anticipated parts of the programme for Congress participants.
The workshop was preceded by the keynote lecture “Twelve goes Thirteen?” delivered by Professor Daniel Eryk Lach, examining the distinction between two situations in which, despite crossing internal EU borders, the social security legislation of one Member State still applies: the posting of workers and employment pursued in two or more Member States.
The Q&A session with ZUS experts, moderated by Marek Benio, followed immediately afterwards. As many participants noted, one hour proved far too short for the number of practical issues and questions related to posting and A1 certificates. The workshop could easily have lasted an entire day — and perhaps next year it will.
This year’s Congress, as in previous editions, was held under the honorary patronage of the President of the Polish Social Insurance Institution. But ZUS’s involvement goes far beyond honorary patronage — the institution has been providing substantive support to ELMC continuously since the very first Congress in 2013.
This year, four experts from the ZUS Department of International Insurance participated in the session.
A growing number of withdrawn A1 certificates
Marta Pardyka presented detailed statistics on A1 certificates, including data broken down by sectors, nationality and legal basis for issuing the certificate — such as posting, work pursued in two Member States or exceptional agreements.
Particular attention was drawn to the number of withdrawn A1 certificates:
– 2023 – 326
– 2024 – 951
– 2025 – 1154
Although this still represents only around 0.136% of all issued certificates, both the number and proportion of withdrawn A1 documents are steadily increasing.
The workshop raised questions about the reasons behind this trend and its practical consequences for companies posting workers abroad. With the number of withdrawals already exceeding one thousand, the need for a deeper analysis of the causes becomes increasingly relevant.
Marta Pardyka also shared practical guidance on how to answer questions contained in the A1 application questionnaire.
The latest CJEU case law on posting
As repeatedly emphasised during the workshop, many of today’s key questions concerning posting are ultimately answered through the case law of the Court of Justice of the European Union.
Tomasz Potaczała presented an overview of three recent CJEU judgments concerning posting and the coordination of social security systems.
The case A. v. GKV Spitzenverband concerned the inclusion of work performed in third countries when calculating the proportion of work pursued in two or more Member States.
In Hakamp, the Court addressed the reference period relevant for assessing the proportion of work carried out in different Member States.
Meanwhile, Team Power Europe focused on the concept of “normal activity” carried out in the sending state — in this case Bulgaria — in the context of temporary work agencies.
Questions from participants and practical problems
For two months before the Congress, organisers collected practical questions from participants concerning posting and A1 certificates.
The questions were addressed by Krzysztof Delert Urban. As every year, the number of practical issues proved too large to cover within a single session.
In his concluding remarks, dr Andrzej Szybkie referred, among others, to the issue of issuing A1 certificates for students under 26 employed under civil law contracts. Despite being excluded from mandatory social security contributions, such individuals remain subject to the legislation of the state providing that exclusion.
At the end of the session, ZUS representatives promised a “second round”, while ELMC organisers announced that even more time would be dedicated to discussions with ZUS experts during the 2027 edition of the Congress.
With experts like these, there is always a sense that more time — and more questions — remain.
📸 A few moments from this part of the programme below
