Find out if you need an A1 Certificate when travelling on business trips to a European country
We often get asked whether or not an A1 certificate is needed when visiting a European country even if it is only for a short business trip.
The regulations around posted workers and social security protocols can often be confusing and vary in their implementations in the various European countries.
Organisations and individuals alike working across borders are understandably concerned about staying compliant and avoiding fines as well as reputational damages.
For this reason, we have decided to write this article with the aim of providing not only an overview on the A1 Certificate itself but also navigating through the complexities surrounding individuals cross border travel and working with a particular focus on short term business trips.
According to the Dutch authorities an A1 certificate
“is a document that states in which country a worker’s social insurance premiums are paid. Without an A1 certificate you or your employee cannot work in some countries“.
More specifically, social security agreements between European countries stipulate that a person can only be subject to social security contributions in one country.
Therefore, the issuance of the A1 Certificate (by the country’s authorities where the worker is employed) is the mechanism through which an individual can be exempted from the social security contributions normally required in the host country where they are being seconded / posted.
Within the framework of the posted worker rules, some European countries (for example France, Italy, Germany and about 15 other countries) also require a notification to be sent to the local social security / labour authorities when an individual arrives (or prior to arriving) on assignment from another European country.
Having said that, France for instance allows an exemption of the posted worker notification provided certain conditions are met, thus making it even trickier to understand how to be compliant.
However, the A1 Certificate itself does not always need to be sent to the host country social security / labour authorities together with the posting notification.
This in turn means that the A1 Certificate, in the countries which do not require it to be sent together with the posting notification, is merely a document which is meant to be kept on file by the employer and carried with by the employee in case of an inspection by the host country labour and/or social security authorities.
The A1 Certificate requirement therefore is very clear cut where an individual goes on assignment for a short to medium period of time.
An A1 Certificate is in fact issued for a maximum of 2 to 5 years (depending on the European country issuing it) after which local social security contributions will become due unless an extension is granted.
What happens though when an individual (employee or self-employed) is only travelling for work to another European country for a very short period of time (say 2-3 days) and they are not even doing actual work but merely attending meetings, fairs or trainings?
We will discuss this issue further below in the subsequent paragraphs.
An A1 Certificate (also known as Portable Document A1 or PD A1) is an official document issued by the social security authorities of an EU/EEA member state or Switzerland that confirms which country’s social security system a worker is covered under when working across borders in Europe.
The certificate serves as proof that social security contributions are being paid in one specific country, thereby exempting the worker from paying duplicate social security contributions in the host country where they are temporarily working.
The fundamental principle behind the A1 Certificate is that under EU social security coordination rules (Regulation EC 883/2004 and 987/2009), a person can only be subject to social security legislation in one country at a time.
Without this mechanism, workers crossing borders would face the risk of paying social security contributions in multiple countries simultaneously.
When issued, an A1 Certificate officially states:
A1 Certificates are issued exclusively by the competent social security authorities of the country where the worker is insured. This could be the country where:
The certificate must be requested from the home country authorities before the worker travels to perform work in another European country, though some countries now allow retrospective applications in certain circumstances.
The situation becomes quite unclear (and also it may differ from country to country) when an individual is travelling for a short period of time (say 2-3 days) as a one-off business trip and they are NOT providing any services in the host country but simply attending seminars, meetings and/or receiving training.
The German Chamber of Industry and Commerce for example argues that “for every business trip, even the shortest, to the EU, the EEA or Switzerland, an A1 certificate is required”.
On the other hand, the EU published a practical guide on the posting of workers in 2019 which confirmed, (see point 2.4) that temporary workers, who do not provide services on their trips, do not fall under the definition of posted workers.
In other words, attending conferences, meetings, fairs, following training etc. would prima facie override what any local government authorities might say and not require an A1 Certificate confirming that social security contributions are in fact being paid in the country where the individual is employed.
However, reading on, the same point 2.4 of the practical guide also mentions that this applies to the administrative requirements and control measures set out in Article 9 of the Posted Workers Directive only and not to social security.
The guide in fact subsequently states that for social security purposes “every cross-border work-related activity (including ‘business trips’) the employer, or any self-employed person concerned, is under the obligation to notify the competent (home) Member State, whenever possible in advance, and obtain a portable document A1 (PD A1)“
The practical guide goes on to say “that obligation covers any economic activity, even if only of short duration. These regulations do not provide for any exceptions for business trips either”.
To make matters even more complicated, some European countries such France, Belgium, Austria, Switzerland and Luxembourg seem to have stepped up controls and enforcement of the A1 Certificate whilst others appear to have, at best, concentrated on particular industries where social security contributions fraud is known to be more widespread (such as the construction industry for instance).
The decision of whether to apply for / obtain an A1 Certificate ultimately can only rest with the employer/s and individual/s concerned and their risk appetite (or lack thereof).
Technically, it appears clear an A1 Certificate is needed regardless of duration, industry, country visited and type of activities carried out whilst in that country.
In reality though, there are many individuals crossing borders across Europe every day without taking with them an A1 Certificate and they have never been asked for one.
On the other hand, we are also aware of workers who were denied access to a site.
Not necessarily by a labour inspection but by the company they were visiting in the host country because the business hosting them did not want to take on themselves any responsibility in connection with a hypothetical accident at work whilst visiting their site / premises without the coverage afforded by an A1 Certificate.
Historically, social security experts would advise to obtain an A1 Certificate when posted workers were spending more than 5% of their working time in a different country.
These days though, there is a growing number of European countries expecting (and ready to enforce upon) posted workers to have an A1 Certificate with them even for a single business trip of a day involving a meeting only.
We would encourage employers and individuals alike to consider the following factors in their decision making process:
1) the country they are travelling to and whether there is evidence of that country enforcing A1 Certificates on short term travellers.
2) the activities carried out and whether they are providing a service or merely attending a seminar, training or meeting.
3) the duration and frequency of the visits in that country (clearly the longer and more often the visits are, the riskier it gets not to have an A1 certificate)
4) the industry the individual operates in and the place they need to be at in the host country (i.e. a construction site no doubt has a much higher chance of being inspected than a two persons meeting at the arrival hall of an airport).
5) the time it takes to obtain an A1 Certificate which in some cases can be weeks if not months, by which time, the individual might have had to go without one anyway.
6) future work-related travel plans as it is possible to get a multi-state A1 Certificate which would avoid having to go through the application process each single time a new European country is visited and make the whole application decision a no-brainer.
To obtain an A1 Certificate, the employer or the individual needs to submit an A1 Form to the authorities of the country where they currently pay social security contributions.
The form itself may have different names depending on the European country.
For example, in the UK, it goes by the name of CA3822 (though this may not be the only form that needs to be submitted to HMRC) and can usually be submitted online or in hard copy by the employer, individual or their agent.
Here it is the full list A1 certificates issuers in each European country.
The processing time can vary significantly not only depending on the country but also when measured against a country’s own official turnaround times for issuing A1 certificates.
In our experience, we have seen anything from 2 weeks to 6 months (and that’s provided there were no issues with the application submitted).
The application itself is relatively straight forward, though we have seen some first-time applicants struggling to answer some of the questions being asked on the A1 Form.
Typically, A1 applicants need to provide details such as date of birth, social security number, residential address, employer’s address, work address in the country they are being posted to, job title, length of stay, etc.
As mentioned earlier, getting an A1 Certificate involves submitting an application to the home country’s social security authorities.
While the process varies by country, the fundamental steps remain similar across Europe.
The general application process follows these steps:
Step 1: Determine which country should issue your A1 Certificate. The certificate must be issued by the country where you currently pay social security contributions. This is typically:
Step 2: Identify the correct application form Each European country has its own form name and process:
Step 3: Gather required documentation Most A1 applications require:
Step 4: Submit your application Applications can typically be submitted:
Step 5: Wait for processing Processing times vary significantly:
Step 6: Receive and verify your A1 Certificate Once issued, check that:
For UK-based workers, the process to obtain an A1 Certificate involves HMRC (Her Majesty’s Revenue and Customs):
Online application (recommended):
Postal application:
Important UK-specific notes:
Germany is one of the most stringent European countries when it comes to A1 Certificate enforcement, with recent guidance emphasizing that certificates are required for virtually all cross-border work activities, regardless of duration.
According to the German Chamber of Industry and Commerce (IHK), “for every business trip, even the shortest, to the EU, the EEA or Switzerland, an A1 certificate is required.” This strict interpretation means that Germany expects workers to carry an A1 Certificate even for:
However, Germany has also shown some flexibility in recent years, allowing retrospective A1 applications in certain cases where workers were unaware of the requirement.
If you are German-based and travelling abroad: The application can typically be submitted:
If you are travelling to Germany from another country: Apply to your home country’s social security authority using their designated A1 application form. You will need to carry the issued certificate with you when entering Germany for work purposes.
When applying for an A1 Certificate related to work in Germany, you’ll typically need to provide:
Processing times in Germany can vary from 2-8 weeks depending on the complexity of the application and the time of year. It’s advisable to apply well in advance of travel, particularly for:
Germany actively enforces A1 Certificate requirements, particularly in sectors such as construction, logistics, and hospitality. Inspections (Kontrolle) can occur at:
While specific penalty amounts can vary, non-compliance can result in fines and the requirement to pay backdated social security contributions in Germany, even if contributions were already paid in the home country.
If you need to apply for an A1 Certificate from Germany or present one to German authorities, note that:
For short-term business trips (conferences, meetings, training), the application process is the same, but you should:
Specify the exact nature of travel:
Consider a multi-state certificate: If you frequently travel for business to multiple European countries, request a multi-state A1 Certificate that:
Timing considerations:
Business travel tips:
When applying for an A1 Certificate, avoid these frequent errors:
If your travel is imminent and your A1 Certificate hasn’t been issued:
Immediate actions:
During travel:
After travel:
Yes, A1 Certificates do expire. The validity period of an A1 Certificate depends on several factors, including the type of posting, the issuing country, and the expected duration of the cross-border work activity.
For short-term postings (up to 24 months): When a worker is posted to another EU/EEA country or Switzerland for a temporary period, the A1 Certificate is typically valid for the duration of the posting, up to a maximum of 24 months (2 years). This applies when:
For longer assignments (24 months to 5 years): Some countries allow extensions beyond the initial 24-month period, potentially up to 5 years total, provided:
For multi-state workers: Workers who regularly work in two or more EU countries can obtain an A1 Certificate valid for up to 3 years, which confirms that they remain subject to the social security legislation of one specific country despite working across borders.
The maximum validity period can vary by issuing country:
When an A1 Certificate expires:
If the work continues beyond the certificate’s validity:
Extension process: To extend an A1 Certificate before it expires:
Automatic expiry situations: An A1 Certificate will automatically become invalid if:
Your A1 Certificate will clearly state:
Always check the expiry date before travelling for work, as an expired A1 Certificate provides no protection against dual social security obligations.
To avoid gaps in coverage:
Once again, there can be significant differences between the various European countries both in terms of the risks of being caught without a valid A1 certificate as well as the fines imposed.
In Austria and Luxembourg penalties could reach up to €10K whereas in France up to €3,300 for instance.
Financial penalties aside, other potential risks involve:
– the reputational damage to the company in the press and/or with the host country’s social security authorities
– the individual may experience “bureaucratic difficulties” whilst they are in a country they are not familiar with
– the actual social security contributions potentially being due in both home and host country
The A1 Certificate (or E101 Certificate as it was known previously) is only issued by the European countries mentioned in the above list of A1 Certificates issuers.
Nonetheless, various countries also have international social security agreements, also known as Totalization Agreements, outside of the European social security framework.Many developed economies such as the US, Japan, Canada, Australia in fact have an equivalent certificates that they can issue as a result of their own social security bilateral agreements.
In such circumstances – i.e. US expat employee moving from the USA to the UK – rather than an A1 Certificate, the posted worker will need to obtain a Certificate of Coverage (in our example, from the US Social Security Administration).
Special attention needs to be paid to posted workers from countries with which the home country has no social security (totalisation) agreement.
In those circumstances, there is a real risk of double social security contributions becoming due.
Nonetheless, this very much depends on the home-host country combination.
For example, if someone is posted to the UK from a non-totalization agreement country, even without a Certificate of Coverage, they could still get an exemption from UK social security contributions for the first 52 weeks.
However, after the initial 52 weeks period is over, double social security contributions (both in the home country as well as in the UK) might be a real possibility.
For NRDs, UK social security contributions are not due provided the employment country has a social security (totalisation) agreement with the host country and an A1 Certificate or Certificate of Coverage has been obtained.
Failing that, again, double social security contributions might be a realistic possibility.
As with regular posted workers, a lot also depends on home-host country combination.
Using again the UK being the host country as an example, thanks to a specific NIC concession for NRDs, UK social security contributions could be avoided on the conditions that:
If an A1 Certificate / Certificate of Coverage cannot be obtained and the above special concession conditions cannot be met, after the initial 52 weeks period is over, UK national insurance contributions will also be due for NRDs.
For social security purposes under EU Regulation (EC) No 883/2004, any work-related activity — including attending meetings, training or conferences — may technically trigger the requirement to obtain an A1 Certificate to confirm which country’s social security legislation applies.
This contrasts with some national instructions that exempt very short visits unless the host country specifically demands it.
In some countries (e.g. Germany), recent guidance allows employers to obtain an A1 Certificate retrospectively if it becomes clear that one was required — for example, if a social security authority or customs inspection later requests it.
However, this retrospective approach does not apply everywhere, and penalties can still be imposed in countries that require presentation up-front.
Yes — enforcement varies significantly.
While some countries (such as Germany) have relaxed their A1 approach to short business trips, others like France, Belgium and Austria continue to strictly require an A1 Certificate on arrival, and non-compliance can lead to fines or inspections.
We are also aware of reports from specific industries (such as the construction industry) where individuals were denied access to sites without proof of a PD A1.
No clear universal definition exists under EU social security coordination rules.
Some national authorities (e.g. Finland) have indicated that short business trips generally do not require an A1 Certificate unless the host state specifically requires one, but the EU practical guide does not set a specific day-count threshold.
Employers need to consider local requirements case-by-case.
If there is uncertainty, employers can choose to apply for an A1 Certificate as a precaution before travel — or, in some jurisdictions, prepare to obtain it retrospectively (as discussed above) if the host country later requests it.
This conservative approach reduces international posting compliance risks, especially given variance in enforcement across Europe.
Yes — the primary purpose of an A1 Certificate is to confirm that social security contributions continue to be paid in the home country, which generally prevents dual contributions in both home and host states.
Without the A1 Certificate, authorities in the host country may require local contributions.
Processing times vary widely by country and time of the year and can range from 2 weeks up to 6 months.
It’s advisable to initiate the A1 Certificate application well before the business trip, especially for first-time applicants or when visiting multiple countries.
Even more so when a work permit, such as a digital nomad visa for employees on international assignments, is tied to the procurement of an A1 Certificate (as it is the case for example with Spain).
Yes — self-employed persons who cross borders for work are generally eligible to apply for an A1 Certificate from their home country authority to confirm social security coverage, just like employed individuals.
This ensures they remain subject to their home social security rules while working abroad.
In principle, yes. In practice, this can be particularly challenging.
In fact, in some countries, such a Portugal who also has an attractive special tax regime for non-habitual residents (NHR), there seems to be no A1 application mechanism for employees of NREs.
This is despite the fact the local social security authorities do receive regular social security contributions from both employer and employees through the non-resident payroll.
Assuming that obtaining an A1 Certificate is not linked to also obtaining a work permit (in which case workers should not start working in the host country), the next best option, if travelling cannot be post-poned, would be to travel with a copy of the A1 Certificate application submission receipt, to at least prove that an A1 Certificate application has been submitted.
It is also advisable to carry proof of registration and payments of social security contributions in the home country (which may include a previously issued A1 Certificate or recent payslips).
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