5 Common Mistakes in Transnational Postings from Romania, and How to Avoid Them

Transnational postings have become a routine part of international projects. Romanian companies send employees abroad to install equipment, deliver construction and technical services, roll out IT systems, transfer know-how, carry out maintenance or temporarily support other group entities. Operationally, it looks simple: the employee stays on the Romanian payroll, works in another country for a while, then comes home.

From a compliance perspective, it is considerably more complex. A single trip can trigger obligations under labour law, the posting of workers rules, social security coordination and the A1 certificate, income tax, payroll, immigration and right-to-work rules, and mandatory host-state notifications. All at the same time.

The scale is significant. The European Labour Authority estimates around 3.6 million postings involving 2.6 million workers across the EU. In June 2026, the Council and the European Parliament reached a provisional agreement on a common e-declaration portal for posted workers, which will simplify how declarations are filed in participating Member States. It will not change what employers must actually assess. That assessment has to happen before the employee leaves, not after the project has started. These are the five mistakes we see most often in practice.

1. Treating every trip as a business trip

The first question is not what the trip is called internally, but what the employee will actually do in the host country. Labels such as business trip, delegation, client visit, training or project support are administrative. Authorities look at the substance of the activity.

There is a real difference between an employee attending a few meetings and one who spends several weeks at a client's site delivering services. To classify the movement correctly, employers should look at:

• the activity actually performed
• the duration of the trip
• where the work takes place
• who receives the services
• the contractual relationship between the companies involved
• how often the employee travels
• the employee's role in the project

Duration matters, but a short stay does not automatically turn service delivery into a business trip. This initial classification determines almost every obligation that follows.

2. Treating the A1 certificate as a formality

A common error is treating the A1 as a document that can be obtained at some point after departure. The A1 confirms which country's social security legislation applies to the employee under the EU coordination rules in Regulation (EC) No 883/2004. Under the posting rule, an employee can remain in the Romanian system for up to 24 months, provided the conditions are met.

Problems typically arise when:

• the project starts before the analysis is done
• the A1 application is prepared too late
• the employee's real situation does not match the documentation submitted
• the employee works regularly in more than one state
• the duration or structure of the project changes mid-way
• the company assumes a Romanian employment contract automatically keeps contributions in Romania

It is also important to be clear about what the A1 does not do. It settles the applicable social security legislation. It does not remove tax, payroll, posting notification or host-state labour law obligations.

3. Checking Romanian rules but not the host state's

A transnational posting always requires analysis in two directions: what must be done in Romania, and what must be done in the country where the employee will work. Romania's own framework, Law 16/2017, transposes the EU Posting of Workers Directive, but each host state applies its own implementing rules.

Depending on the jurisdiction and the activity, the host state may require:

• a posting declaration before work starts
• a designated contact person
• specific documents kept available for inspection
• compliance with local remuneration rules
• compliance with local working time and rest periods
• documentation of the relationship between employer, employee and service recipient
• documents in a language the authorities accept

Construction, transport, installation, industrial and technical projects are often subject to closer scrutiny. A single documentation template used for every country is rarely enough. Each posting should be checked against each host state, and sometimes each project.

4. Assuming that under 183 days means no tax

This is probably the most widespread simplification in international mobility. An employee is going to work in another country for four months, and the first reaction is often that the stay is below 183 days, so the income stays taxable in Romania.

The analysis should not stop there. The 183-day rule operates within the double tax treaty between the two states and the facts of the specific project. Employers should also consider:

• the employee's tax residence
• the actual time spent in the host state and how the relevant period is counted
• who is treated as the employer under the applicable rules
• who bears the salary cost economically
• whether remuneration is recharged to an entity in the host state
• any local payroll or reporting obligations

Separately, the company's activity in the host state may need a permanent establishment risk review. The 183-day threshold is one element of the analysis, not the whole analysis.

5. Handling tax, A1, labour law and immigration in silos

The most damaging mistake is fragmentation. HR requests the A1. Payroll checks the salary. The tax team looks at the 183 days. Travel books the flights. The project manager sets the start date. Immigration is checked only if the employee is not an EU citizen.

Each team can do its own task correctly and the company can still end up non-compliant. An employee may hold a valid A1, have the right to work in the host state and remain employed in Romania, and there may still be a posting notification, tax or payroll obligation in the host country. Equally, a work permit does not resolve social security or tax questions. International mobility is one business process, even if it touches several areas of law.

What a pre-departure process should cover

An effective process starts when the business decides someone will work temporarily in another country. Before mobilisation, the company should establish:

• the type of mobility: business travel, posting, assignment or intra-group transfer
• right to work: can this person perform the planned activity in the host state?
• posted worker compliance: notification, documents and local employment conditions
• social security: where contributions are due and whether an A1 is required
• tax: where salary income may become taxable and what the employer must do
• payroll: whether registration or reporting is needed in the host state
• documentation: what the company must be able to show during an inspection

Only after this analysis should the final mobility file and the actual start date be fixed. The cost of a pre-departure review is almost always easier to control than the consequences of finding a problem mid-project.

How Nestlers Group Supports Transnational Postings

Nestlers Group helps companies that regularly send employees abroad replace case-by-case improvisation with a coordinated internal process. Our Immigration Advisory team classifies each planned movement, confirms right-to-work requirements in the host state and prepares the posted worker notifications and supporting documentation each jurisdiction expects.

Our Payroll and HR Compliance team manages A1 applications and social security analysis, reviews the 183-day and economic employer position alongside the relevant tax treaty, and identifies host-state payroll or reporting obligations before the employee travels. Working across posted workers, social security, tax, payroll, immigration and employment compliance together means each project starts with its compliance structure already settled.

Sources: Council of the EU press release on the provisional agreement for a posted workers e-declaration system, 23 June 2026; European Labour Authority posting estimates cited by the Council, 2026; Directive 96/71/EC as amended by Directive (EU) 2018/957 on the posting of workers; Regulation (EC) No 883/2004 on the coordination of social security systems; Romanian Law 16/2017 on the posting of employees in the framework of transnational services; OECD Model Tax Convention, Article 15