Cross-border enforcement

Enforcing a Portugal judgment in United States

No treaty covers recognition of a Portuguese court judgment in the United States. The US signed the 2019 Hague Judgments Convention but never ratified it, so the judgment route runs through state law alone, state by state. An arbitral award sits on firmer ground: the 1958 New York Convention applies regardless of which state holds the debtor's assets.

Applicable regime

Portugal joined the Hague 2019 Judgments Convention through the European Union's accession, in force since 1 September 2023 [N153]. The United States signed the same convention on 2 March 2022 but has not ratified it, so the convention has never entered into force between the two states [N170]. The critical-date test under Article 16 of the convention only matters once both the origin and destination states are bound to each other; that point is never reached here [N012]. Recognition of a Portuguese judgment therefore proceeds under the law of whichever US state enforcement is sought in, not under any bilateral or multilateral instrument. See enforcement routes into the United States for how this compares across origin jurisdictions.

An arbitral award made in Portugal follows a separate and more established channel. The 1958 New York Convention applies independently of the Hague instruments and covers the United States as a contracting state [N016]. For a dispute that is still open, this is the more reliable route [N172].

What the destination court will check

State courts examining a Portuguese judgment will generally check:

• The Portuguese court had jurisdiction recognizable under the enforcing state's own conflict-of-laws rules.
• The judgment is final and no longer open to ordinary appeal in Portugal.
• The defendant received notice and a genuine opportunity to be heard.
• The judgment was not obtained by fraud.
• Recognition would not conflict with the public policy of the enforcing state.
• The judgment does not order payment of taxes, fines, or other penalties.

These conditions are cumulative. Failing any one of them is enough to block recognition. Which court within a given state actually hears the petition, and how it applies the test, is determined by the applicable procedural rules; there is no fixed answer given how this refusal type is handled.

What will not go through

Judgments ordering payment of Portuguese taxes, customs duties, or administrative fines fall outside any private civil recognition process.

A default judgment entered without proof of valid service under Portuguese procedure, and without a real opportunity to defend, is a frequent point of refusal.

For arbitration, the trap is timing rather than substance. The federal limitation period runs three years from the date of the award [N527], but circuits disagree on what happens after it lapses. The Second Circuit has allowed confirmation of an award previously confirmed abroad, while the D.C. Circuit has held that state limitation law is not displaced by federal arbitration law [N533]. Filing close to that boundary, in the wrong circuit, has ended cases before the merits were reached.

Documents

US courts require documents in English. A certified translation of the Portuguese judgment, the underlying contract, and proof of service must accompany the petition.

Apostille applies to documents entering the United States under the 1961 Hague Convention [N413]. The registry does not carry a separate confirmed entry on the apostille chain from the Portuguese side of this pair; that step is checked case by case.

Timing

Court filing fees in US enforcement proceedings are fixed amounts, not a percentage of the claim [N557].

Limitation periods are set state by state; there is no single federal deadline for a foreign judgment. New York applies the shorter of the Portuguese enforceability period or twenty years, with an accelerated procedure available, summary judgment in lieu of complaint [N528][N529]. Delaware allows fifteen years where Portugal itself sets no fixed term [N530]. California applies the shorter of the Portuguese period or ten years, and is one of only two states, together with Vermont, that never adopted the uniform enforcement act [N531][N532]. The same judgment can face different deadlines depending on where it is filed. See limitation periods across jurisdictions for the underlying comparison.

For an arbitral award, the federal limitation period is three years from the date of the award [N527].

If the primary route is closed

Where the debtor has no reachable assets in the US, recognition elsewhere along the debtor's asset trail can substitute for a US judgment. A settlement confirmed as enforceable during Portuguese proceedings may travel further than the underlying judgment once it qualifies under Article 11 of the Hague 2019 instrument, in states where that convention is actually in force [N014]. That route does not extend to the US given the ratification gap [N170], but it matters where assets sit inside a contracting state.

For disputes still being negotiated, an arbitration clause changes the calculus going forward. An award reaches enforcement through the New York Convention rather than through fifty separate state statutes [N016][N172]. How arbitration clauses interact with non-enforcement covers this in more detail. The reverse direction, enforcing a US judgment in Portugal, runs on different rules again, and judgments leaving Portugal generally follow their own logic depending on destination.

What to do before filing

Before filing, locate the debtor's assets and confirm which US state actually has jurisdiction over them. Filing in the wrong state wastes the fixed fee and buys the debtor time to relocate funds.

Check whether the underlying Portuguese proceeding carries any counterclaim exposure that could resurface once a US court reviews the matter indirectly through a public-policy objection.

Whether an interim measure can freeze assets while the petition is pending is determined by the specifics of the case, not by a general rule stated here. Our cross-border recognition and enforcement work includes a paid asset and route assessment before any filing decision is made.

The firm does not work on a contingency or success-only basis, and its registration can be checked in the public register linked below.