Short answer
Brexit did not create one rule for every cross-border case. First identify the cause of action, UK legal system, relevant dates, chosen-law and chosen-court clauses, defendant's location and country where recognition will be needed.
For applicable law, the Rome I contract and Rome II tort rules were preserved in amended domestic form and are now called assimilated law. They can select EU or other foreign law and usually apply regardless of where proceedings are brought. Jurisdiction is different: for proceedings begun after 31 December 2020, Brussels I bis generally stopped allocating jurisdiction between UK and EU courts. UK courts instead use Hague conventions, special statutes and domestic rules, including forum conveniens.
The Withdrawal Agreement preserves specified EU regimes for proceedings begun before the transition deadline. For newer cases, the 2005 Hague Choice of Court Convention protects qualifying exclusive clauses, and the 2019 Hague Judgments Convention applies for the UK from 1 July 2025 within its temporal and subject limits. Family and insolvency matters use their own domestic and international regimes. A judgment's enforceability should be analysed before proceedings are issued, not after victory.
Start with dates and territorial legal systems
England and Wales, Scotland and Northern Ireland have separate courts, procedural rules and some distinct private-international-law rules. A clause selecting “UK courts” may therefore be uncertain; name the legal system and court.
Under the EU–UK Withdrawal Agreement, Brussels I bis recognition and jurisdiction rules continue for relevant civil proceedings instituted before 11 p.m. UK time on 31 December 2020. Parallel transitional rules cover Brussels IIa family proceedings, maintenance and EU insolvency proceedings opened before the deadline. Later procedural steps do not necessarily move an old case into the new regime, but the precise transition provision must be checked.
The European Union (Withdrawal) Act 2018 preserved selected EU rules. The Retained EU Law (Revocation and Reform) Act 2023 renamed surviving retained EU law “assimilated law” and changed parts of its interpretive framework from 1 January 2024. It did not revoke Rome I or Rome II wholesale.
Contracts: governing law and forum are separate
Rome I, as amended for domestic operation, generally governs contractual choice of law. Its starting point is:
“A contract shall be governed by the law chosen by the parties.”
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The choice must be express or clearly demonstrated. Without one, Article 4 uses contract-specific connecting factors—often the seller's, service provider's, franchisee's or distributor's habitual residence—with an escape for a manifestly closer connection. Mandatory forum rules and public policy can override the selected law. Consumer and employment contracts retain protections that a choice cannot remove. Capacity, company law, arbitration agreements and some pre-contractual questions may fall under other rules.
A governing-law clause does not confer jurisdiction, and a jurisdiction clause does not necessarily choose substantive law. Since Brexit, an English court ordinarily asks whether the defendant can be served within the jurisdiction or whether a CPR Practice Direction 6B gateway permits service abroad, whether there is a serious issue to try and whether England is the proper place. Scotland and Northern Ireland use their own procedural routes. illustrates the tort damage gateway and service-out analysis.
Under the , a qualifying exclusive choice-of-court agreement in a civil or commercial matter generally requires the chosen Contracting State court to hear the dispute, other Contracting State courts to suspend or dismiss, and resulting judgments to be recognised. Consumer and employment contracts, insolvency, family matters and several other subjects are excluded. Asymmetric and non-exclusive clauses may fall outside it. UK law treats Convention coverage as continuous from 1 October 2015, but temporal treatment of clauses made before the UK's independent accession took effect can require separate analysis in the foreign forum.
Arbitration is separate. The Arbitration Act 1996, the chosen seat and the New York Convention normally govern, not Brussels I bis or the Hague Judgments Convention. The law governing the arbitration agreement may differ from the main contract; sets out the English common-law analysis.
Torts: Rome II usually selects the law, not the court
Rome II's general rule is the law of the country where direct damage occurs, irrespective of where the event causing it or indirect consequences occur. A common habitual residence or a manifestly closer connection can displace that rule. Special rules address product liability, unfair competition and competition restrictions, environmental damage, intellectual property and industrial action. A post-event choice of law is possible, and commercial parties can sometimes agree in advance under defined conditions.
Rome II excludes important subjects, including privacy and personality rights such as defamation. Domestic conflict rules then apply; in England and Wales, defamation remains outside Part III of the Private International Law (Miscellaneous Provisions) Act 1995. The applicable-law answer does not establish jurisdiction: service gateways, submission, exclusive jurisdiction and forum conveniens still need separate treatment.
Recognition of civil and commercial judgments
The entered into force for the UK on 1 July 2025. It can require recognition and enforcement of a civil or commercial judgment where a Convention jurisdictional basis exists—for example, habitual residence, relevant branch activity, express consent or place of contractual performance. It applies only where the Convention was effective between the state of origin and requested state when the original proceedings were instituted. It excludes family, insolvency, defamation, much intellectual property, arbitration and other listed fields, and permits refusal on grounds including defective notice, fraud, public policy and inconsistent judgments.
The 2019 Convention does not allocate jurisdiction before judgment and does not require an exclusive clause. The 2005 Convention remains the more specific route for qualifying exclusive-clause judgments. Always check declarations and the territorial unit involved.
Outside an applicable convention, the Administration of Justice Act 1920 and Foreign Judgments (Reciprocal Enforcement) Act 1933 provide registration for designated countries and judgments. Otherwise, English common law ordinarily requires a fresh claim on a final and conclusive foreign money judgment. The foreign court must have jurisdiction under English recognition rules, commonly because the defendant was present when proceedings began, submitted, claimed or agreed to that forum. Fraud, natural justice, public policy and inconsistency can defeat enforcement. rejected a special, broader enforcement rule for foreign insolvency judgments.
Family matters use specialised conventions
For new divorce proceedings, domestic statutes now determine UK jurisdiction, principally domicile and habitual-residence rules under the Domicile and Matrimonial Proceedings Act 1973 and corresponding territorial legislation. Recognition of overseas divorces is governed mainly by Part II of the Family Law Act 1986 and the 1970 Hague Divorce Recognition Convention where applicable. Financial relief, maintenance and divorce jurisdiction are distinct; proceedings in different UK legal systems can also require allocation rules.
For parental responsibility and child-protection measures, the 1996 Hague Convention generally gives primary jurisdiction to authorities of the child's habitual residence and provides cooperation, recognition and enforcement. Wrongful removal is governed by the 1980 Hague Child Abduction Convention, implemented by the Child Abduction and Custody Act 1985. Its objects include:
“to secure the prompt return of children wrongfully removed to or retained in any Contracting State”
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Return is not a final custody decision, and the Convention contains tightly interpreted exceptions. The 2007 Hague Child Support Convention provides central-authority cooperation and recognition and enforcement of maintenance decisions. Domestic reciprocal-enforcement rules cover other relationships. The child's habitual residence, date of removal, Convention relationship between states and any protective issue must be established urgently.
Cross-border insolvency has no single replacement for the EU Regulation
The EU Insolvency Regulation 2015/848 generally no longer governs new UK proceedings, though the Withdrawal Agreement preserves it for qualifying pre-transition proceedings. Newer cases use a combination of domestic law and cooperation regimes.
The Cross-Border Insolvency Regulations 2006 implement the UNCITRAL Model Law in Great Britain, allowing recognition of foreign main or non-main proceedings and specified assistance; Northern Ireland has parallel regulations. Recognition depends particularly on the debtor's centre of main interests or establishment and does not automatically enforce every judgment issued within the foreign case. Section 426 of the Insolvency Act 1986 permits assistance between UK courts and designated countries or territories. Common-law recognition and assistance remain bounded by jurisdiction, statute and public policy; modified universalism cannot invent powers Parliament withheld.
Practical checklist
Record when proceedings or insolvency opened and when any clause was agreed. Separate governing law, jurisdiction, service, parallel proceedings and recognition. Identify every relevant country and UK legal system, then test the Withdrawal Agreement, specialised convention, reciprocal statute and domestic fallback in that order. Review clause scope and exclusivity, consumer or employment status, mandatory rules, limitation and assets. If enforcement matters, obtain advice in both the proposed forum and the asset state before filing.
Conclusion
Post-Brexit UK private international law is a layered system, not a return to common law for everything. Rome I and II usually answer applicable law; Hague instruments, transition rules and domestic procedure answer forum and enforcement; family and insolvency have separate networks. Dates, subject exclusions and the exact territorial system often determine the outcome.
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.