In this article, you will learn:

• the fundamental differences between a sole proprietorship and a company;

• the characteristics, advantages, and disadvantages of the most common (and more specific) company types;

• What are the key criteria for choosing the legal structure best suited to your business and its long-term development?.

Basic concepts

Among the most common legal forms in Luxembourg are the sole proprietorship, the private limited liability company (S.à r.l.) and its simplified version (S.à r.l.-S), and the public limited company (S.A.).

In brief:

• Sole proprietorship (also referred to as freelance or self-employed status)
  Suitable for low-risk individual projects or secondary activities. It involves limited formalities and relatively simple administration. However, the entrepreneur’s liability is unlimited.
• S.à r.l.-S (simplified private limited company): Limits shareholders’ liability to a certain extent and follows the S.à r.l. regime, but with lower incorporation costs since no notary is required. The required share capital ranges from €1 to €12,000, making it accessible for entrepreneurs with limited start-up funds.
  However, it is not suitable for capital-intensive projects and remains subject to the same administrative obligations as a traditional S.à r.l.
  • Specific features:
    Only natural persons may be shareholders (no corporate shareholders).
    One individual may hold shares in only one S.à r.l.-S.
  • Good to know: 5% of annual net profit must be allocated to a mandatory reserve until the combined share capital and reserve reach €12,000 and the conversion into a standard S.à r.l. is not automatic once this threshold is reached; a notarial deed is required.
• S.à r.l. : it is the most popular legal structure in Luxembourg. It limits liability and allows a controlled circle of shareholders (individuals or companies) with a relatively simple governance framework.
  Minimum share capital: €12,000 (fully paid in cash or in kind).
  Notarial incorporation is mandatory.
• S.A.: recommended for larger businesses or companies targeting rapid and/or significant growth. It offers greater flexibility for transferring shares and attracting investors, though governance requirements are more complex.
  Minimum share capital: €30,000, of which 25% (€7,500) must be paid in at incorporation.
  Notarial deed required.

Expert insight: evaluating your options

“Legal structure is often not the first concern of project holders. Yet it is one of the first essential decisions in starting a business, and it must be made with a clear understanding of its legal, administrative, and tax implications.

A poor choice can become costly and constrain your management or long-term prospects. For example, many entrepreneurs set up an S.à r.l. or S.à r.l.-S without fully understanding that both are companies subject to strict accounting, tax, and social security obligations. When these obligations are underestimated, entrepreneurs may face public debts or penalties within months or years. For example, many entrepreneurs set up an S.à r.l. or S.à r.l.-S without fully understanding that both are companies subject to strict accounting, tax, and social security obligations. When these obligations are underestimated, entrepreneurs may face public debts or penalties within months or years.

Others choose a sole proprietorship to avoid incorporation costs, without realising that their personal assets — including, depending on the marital regime, those of their spouse — may be exposed. Or that becoming self-employed may affect existing social rights, such as parental leave previously linked to salaried employment.

My recommendation: seek personalised advice to assess your options thoroughly, considering both your project characteristics and your personal and professional situation.”
— Guylaine Marchi Hanus, Founder of EIS

Key selection criteria

As we have seen, every situation is different. While some answers may emerge quite clearly, there is no “standard” solution when it comes to choosing a legal structure — it is truly a case-by-case decision.

There is no standard answer. Each situation requires case-by-case analysis.
A poor structural choice can create obstacles even before the business becomes operational — for example when opening a professional bank account or securing financing.

• Example 1: an S.à r.l.-S with €1 capital operating an animal boarding business. The lack of capital may undermine credibility with suppliers or banks, since no financial cushion exists in case of default.
• Example 2: an S.à r.l.-S with €1,000 capital for an on-site restaurant concept. Without sufficient capital, covering rent, salaries, equipment, and initial inventory becomes unrealistic. The structure may appear financially incoherent or risky.

EIS insight: for lower-investment activities such as consulting services, the S.à r.l.-S may be appropriate.

The EIS mini-checklist

Here are the key points to consider when choosing the legal structure that will work best for you.

Consider the following:

• the nature of your activities and associated risks;
• whether you are starting alone or with partners;
• your growth trajectory: rapid or gradual, local or international, investor involvement, subsidiaries
  Governance preferences: shareholder control vs. capital openness;
• governance preferences: shareholder control vs. capital openness;
• revenue expectations and taxation, including social security contributions and whether the activity is primary or secondary;
• liability exposure and managerial obligations;
• credibility toward professional partners and financial robustness;
• administrative complexity and flexibility in decision-making.