A Barcelona-based IT services company won a multi-year contract to deliver on-site technical support at a Warsaw client's headquarters. Within weeks, three Spanish engineers were due to begin work in Poland. The company had no Polish entity, no local payroll, and no prior experience with Polish employment formalities. The clock was running.

When a Spanish employer posts workers to Poland without a Polish establishment, EU coordination rules allow those workers to remain in the Spanish social security system – provided a valid A1 certificate is obtained before the posting begins. The certificate is issued by the Spanish Social Security Treasury (Tesorería General de la Seguridad Social, TGSS) and must be presented to Polish authorities on request. Failure to hold a valid A1 certificate exposes both the employer and the host-country recipient to back-contributions and administrative sanctions.

This case study walks through the background, the strategy our team applied, the procedural steps taken, and the lessons that any Spanish business sending staff to Poland can apply directly. The matter was handled by our employment practice in Warsaw during spring 2025.

What was the background of this posting?

The Spanish company employed all three engineers under standard Spanish employment contracts. Their assignment to Warsaw was structured as a temporary posting under EU Regulation 883/2004 on the coordination of social security systems. The posting was expected to last 18 months – within the 24-month maximum that EU coordination law permits for single-state coverage.

The client had assumed, incorrectly, that because the workers held EU citizenship no further formalities were required. That assumption is one of the most common and costly mistakes Spanish companies make when entering the Polish market. EU free movement removes immigration barriers. It does not remove social security coordination obligations or Polish labour notification requirements.

Two specific gaps emerged on review. First, no A1 certificates had been applied for. Second, the company had not submitted the mandatory posting notification to the Chief Labour Inspectorate (Państwowa Inspekcja Pracy, PIP) – Poland's primary labour enforcement body – at least 30 days before the workers' start date. Both gaps needed to be closed before the engineers arrived on site.

What strategy did the team apply?

Our employment practice in Warsaw assessed the matter within 48 hours of instruction. The core strategic decision was sequencing: the A1 application to TGSS in Spain had to run in parallel with the PIP notification in Poland, not sequentially. Waiting for the certificate before notifying PIP would have pushed the notification past the 30-day deadline.

We structured the work across three tracks. First, we drafted the PIP notification package – including the required details of the posting terms, remuneration, and the liaison person appointed in Poland. Second, we coordinated with the Spanish company's HR team to compile the TGSS application documents: payroll records, proof of habitual employment in Spain, and the posting agreement. Third, we prepared a compliance checklist for the Warsaw host entity, which had its own obligations under Polish Posted Workers Act (ustawa o delegowaniu pracowników w ramach świadczenia usług).

The strategy also addressed a forward-looking risk. If the posting extended beyond 24 months, the workers would fall out of the A1 framework. We flagged this at the outset and built a review trigger into the engagement letter at the 18-month mark – giving the client a six-month window to reassess before any lapse in coverage.

We secured timely A1 certificates for all three engineers and filed the PIP notification within the statutory window for a client in the Mazowieckie region (spring 2025). The host entity avoided any exposure to joint-and-several liability for outstanding social contributions.

How did the process unfold?

The TGSS application was submitted electronically through Spain's social security portal. Processing took approximately 15 working days – within the standard timeline for straightforward postings. Each certificate was issued on a per-worker basis and specified the posting period, the receiving country (Poland), and the applicable Spanish social security legislation.

The PIP notification was filed online through Poland's dedicated posting portal. Polish law requires the notification to identify the posted workers, the host entity, the nature of the work, and the anticipated duration. Our team submitted the notification 31 days before the engineers' first day on site – one day inside the deadline, but sufficient.

One complication arose mid-process. TGSS requested supplementary payroll documentation for one engineer who had changed roles within the Spanish company three months earlier. This is a known TGSS risk factor: a recent internal transfer can raise questions about whether the worker was genuinely habitually employed in Spain. We provided a detailed employment history letter from the Spanish HR director, and the certificate was issued without further delay.

For a related perspective on how the same A1 framework applies in a different cross-border context, see our case study on posted workers from Cyprus to Poland – A1 certificates.

What lessons does this matter carry?

Three lessons stand out for any Spanish business considering a posting to Poland.

  • Start both processes simultaneously. The TGSS application and the PIP notification must run in parallel. Sequential handling almost always produces a missed deadline.
  • Check the 24-month ceiling early. Postings that drift past this limit lose A1 protection. The worker then falls into the Polish social security system – triggering registration with the Social Insurance Institution (Zakład Ubezpieczeń Społecznych, ZUS) and back-contributions from the date of the breach.
  • Audit the host entity's obligations. The Polish recipient company is not a passive bystander. Under Polish posted workers legislation, it carries joint-and-several liability for outstanding remuneration and social contributions if the Spanish employer defaults.
  • Document habitual employment carefully. TGSS scrutinises recent role changes. A clear employment history letter, prepared before submission, prevents supplementary requests that add two to three weeks to processing time.

The same procedural logic applies to Spanish companies sending workers to Poland in manufacturing, construction, or professional services – not only IT. For further context on how Spanish businesses protect their intellectual assets when operating in Poland, see our analysis of IP protection strategy for Spain tech companies in Poland.

Separately, for Swiss-based employers facing structurally similar A1 questions – including the additional complexity of non-EU social security coordination – our case study on posted workers from Switzerland to Poland – A1 certificates provides a useful comparison.

What to prepare before a posting from Spain to Poland:

  • Proof of habitual employment in Spain (payroll records, employment contract, social security contribution history)
  • Posting agreement signed by employer and worker
  • Details of the Polish host entity for the PIP notification
  • Liaison person appointed in Poland with a Polish address
  • Anticipated posting duration confirmed against the 24-month ceiling

Each of these items should be assembled before the TGSS application is submitted. Missing documentation is the single most common cause of processing delays – and delays that push past the PIP notification deadline cannot be corrected retroactively.

Specific circumstances of your posting – including worker nationality, dual employment, or planned extensions – require individual assessment before the application is filed. Acting after the workers arrive forfeits the procedural protections that advance filing provides.

If your Spanish company is planning a posting to Poland and needs the A1 and PIP notification processes managed in parallel, contact info@kordeckipartners.com. Our employment practice in Warsaw will review your posting structure, coordinate with your Spanish HR team, and file all required documentation within the statutory windows.

Frequently asked questions

Q: Does a Spanish worker posted to Poland need a work permit?

A: No. Spanish nationals are EU citizens and benefit from the free movement of workers within the European Union. No work permit Poland requirement applies to them. The A1 certificate addresses social security coverage only – it is not an immigration document and does not substitute for the PIP posting notification, which remains mandatory regardless of nationality.

Q: What happens if the A1 certificate is not obtained before the posting starts?

A: Polish authorities – including ZUS and PIP – may treat the worker as subject to Polish social security from the first day of work. This triggers retroactive contribution obligations, potential penalties, and loss of the coordination benefit that the A1 framework provides. Retroactive A1 applications are possible in limited circumstances but are subject to TGSS discretion and do not guarantee full retroactive coverage.

Q: Can the posting be extended beyond 24 months?

A: Yes, but only through a formal agreement procedure between the Spanish and Polish competent authorities. The employer must apply before the original A1 certificate expires. Extensions are not automatic and are assessed on a case-by-case basis. If the extension is denied or not applied for in time, the worker must be registered with ZUS and Polish contributions become due prospectively.

About KORDECKI & Partners

KORDECKI & Partners is a law firm based in Warsaw and Krakow, advising business clients across 30 jurisdictions. Our team combines expertise in Polish and international law with a practical approach to employment, global mobility, and posted workers compliance. We work with Polish entrepreneurs, foreign investors, and in-house legal teams. To discuss your situation, contact info@kordeckipartners.com.

Disclaimer: This publication is provided for informational purposes only and does not constitute legal advice. The information herein should not be relied upon as a substitute for professional legal counsel tailored to your specific circumstances. KORDECKI & Partners assumes no liability for actions taken or not taken based on the contents of this material. For advice regarding your particular situation, please contact info@kordeckipartners.com.