Short answer
For contractual obligations in EU civil and commercial matters, Regulation (EC) No 593/2008—the Rome I Regulation—usually begins with the law expressly or clearly chosen by the parties. If there is no valid choice, Rome I supplies rules for particular contract types, followed by characteristic performance and a closer-connection test.
A choice-of-law clause is not an escape from every compulsory rule. Four limits must be kept separate:
- a wholly domestic or wholly EU-centred situation retains certain rules that the parties cannot contract out of;
- consumers, employees and some carriage and insurance parties receive special protection;
- Article 9 permits narrowly defined overriding mandatory provisions of the forum and, in more limited circumstances, the country of performance;
- Article 21 allows refusal of foreign law only where applying a provision would be manifestly incompatible with the forum's public policy.
Special EU conflict rules can also take priority. The answer therefore depends not just on the clause, but on the contract type, where the parties and performance are located, which court hears the dispute, and the purpose and scope of the supposedly mandatory rule.
Rome I first asks whether the contract is within scope
Rome I applies to contractual obligations in civil and commercial matters where there is a conflict of laws. It excludes specified subjects, including arbitration and choice-of-court agreements, company organisation, family relationships, matrimonial property and succession. Jurisdiction and governing law are separate questions: a court can have jurisdiction while applying another country's law.
The Regulation can select EU or non-EU law. It applies to contracts concluded as from 17 December 2009; older contracts generally remain under earlier conflict rules. Denmark is not bound by Rome I.
Party choice is the starting point
Article 3(1) states:
“A contract shall be governed by the law chosen by the parties.” —
The choice must be express or clearly demonstrated by the contract or circumstances. It may cover the whole contract or only part of it, and the parties can change it later without prejudicing formal validity or third-party rights. Consent to the choice itself is tested under Rome I's validity rules.
Choosing a country's law normally selects its substantive rules, not its conflict rules: Article 20 excludes renvoi. A governing-law clause does not itself select a court.
Article 3 contains two anti-evasion rules. If all other relevant elements are in one country, choosing another country's law cannot displace the first country's provisions that cannot be derogated from by agreement. If all other relevant elements are in one or more Member States, choosing non-Member-State law cannot displace non-derogable EU rules, where appropriate as implemented by the forum.
These are ordinary mandatory rules within the particular relationship. They are not automatically the more exceptional “overriding mandatory provisions” in Article 9.
Without a choice, contract type and connection decide
Article 4 gives fixed connecting factors for common contracts. A sale is generally governed by the seller's habitual-residence law; services by the service provider's; a franchise by the franchisee's; and distribution by the distributor's. Immovable-property contracts usually follow the property's location.
If no listed category fits, or several fit, the default is normally the habitual residence of the party making the contract's characteristic performance. A manifestly closer connection to another country displaces those defaults. If neither the category nor characteristic-performance rules resolve the question, the law of the country most closely connected applies.
Special rules in Articles 5–8 govern carriage, consumer, insurance and employment contracts. Other EU legislation may contain its own conflict rule and take priority under Article 23. Existing international conventions can also matter under Article 25. A sound analysis therefore checks specialist instruments before treating Article 4 as the final answer.
Consumers and employees keep non-derogable protection
Where a professional directs activities to a consumer's country and the contract falls within those activities, Article 6 generally uses the law of the consumer's habitual residence. The parties may choose another law, but cannot deprive the consumer of non-derogable protection under the law that would otherwise apply.
In Case C-191/15, Verein für Konsumenteninformation v Amazon EU, the Court of Justice considered an online seller's standard term choosing the seller's home law. It held that such a term is unfair if it misleads the consumer into believing that only the chosen law applies without explaining the retained Article 6(2) protection:
“he also enjoys the protection of the mandatory provisions of the law that would be applicable in the absence of that term” —
The judgment does not invalidate every consumer choice-of-law clause. The clause cannot erase statutory protection, and its presentation can be assessed under EU unfair-terms law.
FB v European Lotto and Betting, C-440/23, illustrates the consequence. The terms chose Maltese law, but the referring court treated German law as applicable under Article 6(2). The Court did not itself reselect the law; it confirmed that Articles 10(1) and 12(1)(e) leave the contract's validity and consequences of nullity—including restitution—to the applicable contract law.
Article 8 uses a parallel protective structure for employees. A chosen law cannot remove non-derogable protection under the law that would apply without the choice—normally the country in which, or from which, the employee habitually works, subject to the Regulation's fallback and closer-connection rules.
Overriding mandatory provisions are a narrow category
Article 9(1) defines the category by function, not merely by a national label:
“provisions the respect for which is regarded as crucial by a country for safeguarding its public interests” —
The provision must be so important to the country's political, social or economic organisation that it applies to every situation within its scope regardless of the law otherwise governing the contract. Recital 37 says this concept should be construed more restrictively than provisions that parties simply cannot derogate from.
The forum may apply its own qualifying overriding mandatory provisions. Article 9(3) gives a narrower discretion for the law of the place where contractual obligations must be or were performed: effect may be given only where those provisions render performance unlawful. The court must consider their nature and purpose and the consequences of applying or not applying them.
In Case C-135/15, Nikiforidis, the Grand Chamber confirmed that the Article 9 list is controlled. Rules of another country, outside the forum and place of performance, cannot be applied as legal rules. They may still be considered as facts if the governing national contract law permits that:
“not precluding it from taking such other overriding mandatory provisions into account as matters of fact” —
That distinction prevents a court from recreating a broad foreign-mandatory-rule exception through another label.
A national rule is not overriding merely because it is mandatory
Case C-184/12, Unamar, concerned the predecessor Rome Convention, not Rome I, and a national law giving commercial agents more protection than an EU directive required. The Court held that displacing the chosen law required a detailed assessment of the national rule's terms, structure, legislative circumstances, nature and objective. The forum legislature must have regarded the additional protection as crucial.
Although the dispute was governed by the Rome Convention, the judgment expressly used Rome I Article 9(1)'s definition as consistent context. Its continuing lesson is limited but important: neither a mandatory label nor a policy preference is enough. The exception must be interpreted strictly so that party choice and uniform EU conflict rules retain practical effect.
Public policy is a last-resort refusal rule
Article 21 is different from Article 9. It does not apply a forum rule because that rule always governs. It allows the court to refuse a particular result of the law designated by Rome I:
“only if such application is manifestly incompatible with the public policy (ordre public) of the forum.” —
“Manifestly” and recital 37's reference to exceptional circumstances set a high threshold. A difference between the chosen law and forum law, even a material one, is not enough. The court should identify the particular foreign provision and the fundamental forum policy that its application would plainly violate. Article 21 is not a general licence to replace foreign law with the result the forum prefers.
A practical sequence
- Confirm that the obligation is contractual, civil or commercial, and within Rome I's material and temporal scope.
- Separate governing law from jurisdiction and test the choice's consent, form and scope.
- Without a choice, classify under Articles 4–8 and test any closer connection.
- Check protected-party rules, Article 3 anti-evasion rules and specialist EU or treaty rules.
- For Article 9, identify the forum, place of performance, precise rule, territorial scope and public interest it safeguards.
- For Article 21, identify the concrete foreign-law result and why incompatibility would be manifest.
Conclusion
Rome I generally honours a valid choice of law. Without one, contract-specific connecting factors, characteristic performance and closer connection determine the answer. But a clause cannot remove protected-party rules, the anti-evasion limits in Article 3, qualifying overriding mandatory provisions, specialist EU conflict rules or the narrow public-policy safeguard.
Sources
This article provides general legal information, not advice for a specific matter. Laws, facts and procedural deadlines may change the result. Follow the linked primary sources and obtain local advice before acting.