Document legalisation is the process that prepares a UK document for use in another country.

In the UK, the FCDO Legalisation Office legalises a document. It checks that the signature, seal or stamp on the document is genuine and was issued by a person or authority authorised to do so.

If the checks pass, the FCDO Legalisation Office attaches a certificate called an apostille to the document. Some countries also need their embassy in the UK to add a final stamp.

The authority abroad can then trust that the document came from a genuine official source and has been verified.

The rest of this page explains why legalisation exists, what it proves and how it works.

Why legalisation exists

The UK’s legal authority stops at the border. The UK government, notaries, solicitors, registrars and other public officials can issue and certify documents for use in the UK.

But UK stamps, seals, signatures and certifications have no official authority in Spain, Brazil or the UAE.

Once a UK document crosses a border, the receiving authority has no practical way to verify its origin. It can’t check whether the professional who signed it is still licensed, or whether the stamp is a careful forgery.

Every country has its own system for issuing and certifying documents. So an overseas authority may need official confirmation that the signature, seal, or stamp belongs to the person or organisation named.

Legalisation provides that confirmation.

In the UK, the FCDO Legalisation Office does this. It verifies the signature, seal or stamp on the document against its records. It confirms that the person who signed or stamped the document had the authority to do so.

Once it confirms this, it issues a certificate called an apostille.

Before 1961, a document needed a chain of authorisations, usually ending at the destination country’s embassy. The Apostille Convention replaced that chain with a single certificate. Countries that have joined the Convention recognise the apostille because every apostille follows the same format.

In short, legalisation is one government vouching for its own officials to another. The foreign authority doesn’t need to know who signed your document. It only needs to trust the UK government.

That is why an original document is legalised in the country that issued it. A UK document is legalised in the UK, and a Spanish document is legalised in Spain.

“It’s already an official UK document. Why does it need legalising?”

It’s a fair question. A GRO birth or marriage certificate, an ACRO police certificate or a DBS certificate is already an official UK document. But it is official in the UK. An overseas authority can’t check UK records, so it can’t confirm that the signature, seal, or stamp is genuine.

Being officially issued and being authenticated for use abroad are two separate things.

The issuing organisation provides the document. Legalisation adds an official UK confirmation, in a format the overseas authority recognises, that the signature, seal or stamp is genuine.

It doesn’t mean anyone doubts your document. It lets another country rely on it. Whether you need it depends on the rules where you will use the document, so check with the organisation that asked for it.

What the Legalisation Office checks

The Legalisation Office doesn’t confirm that what a document says is true, but it does read it. Depending on the document, it checks what it is, who issued it, and how it has been certified. It also verifies every signature, seal or stamp against its records.

Which mark it checks depends on the document:

Document	Whose mark is checked
Birth, marriage, and death certificates	The registrar or the General Register Office. Only originals and official certified copies are accepted, never photocopies.
Court orders and court documents	The court’s wet-ink signature and its stamp or seal
Medical reports and letters	The wet-ink signature of a doctor registered with the General Medical Council
Companies House and HMRC documents	The wet-ink signature of a Companies House or HMRC official
Degrees, diplomas and other qualifications	The signature and seal of the FCDO-registered solicitor or notary who certified the document
Documents with no recognised official mark, such as powers of attorney and contracts	The signature and seal of the FCDO-registered solicitor or notary who certified or notarised the document

Before the Legalisation Office issues an apostille, they make three checks:

1
Can this document be legalised? The office reads the document to see what it is and who issued it. It must be a UK document of a type the office accepts. Some documents are refused outright, such as original passports, photocopies of birth, marriage and death certificates, and Med 3 sick notes. For qualifications, the office also checks that the issuing body is on an approved UK education register, such as the Office for Students or Ofqual register. A partnership with a registered university is not enough.
2
Is the mark genuine? The office compares the signature, seal or stamp against its records. It confirms that the person held that role and had the authority to sign or stamp the document. A solicitor or notary must be registered with the FCDO; a valid practising certificate alone is not enough.
3
Has it been applied correctly? The office checks that every required element is present, complete, and error-free. That includes the certification wording, which must state whether the document is an original or a true copy. A genuine signature is not enough if anything else is missing or wrong.

If any check fails, the office won’t issue an apostille, and the document cannot be legalised. Common reasons include:

a qualification from a provider that isn’t on an approved register
a solicitor or notary who isn’t registered with the FCDO
a photocopy of a birth, marriage or death certificate
a medical document without the doctor’s wet-ink signature
a missing or incorrect date
a seal that is not fully embossed, or a missing stamp
a signature or stamp the office cannot match to its records
certification wording that is incomplete or contains errors

For the full list of what the FCDO accepts and refuses, see Documents the FCDO can legalise.

An example: a degree certificate

A degree certificate is signed on behalf of the university, not by a UK public official. The Legalisation Office cannot verify that signature, so the degree first needs a signature it can verify.

That is the role of an FCDO-registered solicitor or notary. GOV.UK counts both as public officials for legalisation. They certify the degree, or a copy, and add their own signature and seal.

The Legalisation Office then checks two things: that the solicitor’s certification is genuine and correctly completed, and that the university is on an approved UK education register. If both checks pass, it attaches the apostille to the solicitor’s certification.

Three parties confirm three different things. The university awarded the degree. The solicitor certified the document. The Legalisation Office confirmed the solicitor’s certification and the university’s registration.

What legalisation proves, and what it doesn’t

The checks above determine whether a document is eligible for legalisation.

The apostille itself certifies three things: the signature is genuine, the person signed in their official capacity, and any seal or stamp is authentic.

It does not prove:

That the contents are true. A legalised degree does not prove you passed your exams. That still rests on the university’s word.
That the document is legally valid. Legalising a contract does not make it enforceable.
That the recipient will accept it. An employer abroad still decides whether your degree meets its requirements.

This is the most common misunderstanding. The Legalisation Office may read a document to decide whether it can be legalised, for example, to check who issued a qualification. But the apostille never certifies that what the document says is true.

The chain of trust

Legalisation works as a chain, with each link vouching for the one before it.

1
The signatory. A UK official issues the document, or a solicitor or notary certifies it.
2
The FCDO Legalisation Office. It checks the signature against its records and attaches an apostille.
3
The destination country’s embassy, if required. It checks the FCDO’s signature and adds its own stamp.

The foreign authority only needs to trust the last link, because each earlier link has been checked by the one after it.

Two systems: apostille or embassy legalisation

You can legalise a UK document in one of two ways. Which one depends on the country where you will use it.

This is because of the 1961 Apostille Convention. Countries that have joined it accept each other’s apostilles without further checks. Countries that haven’t joined still require their own embassy to authenticate the document, as every country did before 1961.

The Convention now has 130 Contracting Parties, including a few that have joined but for which it has not yet taken effect.

So, the two routes are:

1
Apostille only. If the Convention applies in the destination country, legalisation is complete once you attach the apostille. Spain, Italy, the USA and China are examples.
2
Apostille plus embassy legalisation. If the destination is not covered, the apostille is the first step. The destination country’s embassy in the UK then legalises the FCDO’s signature. The UAE is an example.

In the UK, the Legalisation Office issues an apostille regardless of the destination. What changes is whether an embassy step follows.

Membership changes, so check the current position before you start. Thailand, for example, has joined, but the Convention takes effect there only on 28 February 2027.

Sometimes neither step is needed. Some countries have agreements that exempt certain documents. The organisation asking for your document can tell you what it requires.

Did Brexit change anything?

Legalisation isn’t new, and Brexit didn’t create it. The UK has issued apostilles under the Convention since 1965. From February 2019 to December 2020, an EU rule allowed certain UK documents, such as birth, marriage, and criminal record certificates, to be used in EU countries without an apostille. That exemption ended with the Brexit transition period, so those documents need an apostille again.

What a legalised document looks like

A completed legalisation leaves a visible result. What you get back depends on the route you choose.

The apostille

On a paper document, the apostille is a certificate attached to the document you submitted. Every apostille follows the same model, set by the Convention, with ten numbered fields:

1
The country that issued the apostille
2
The name of the person who signed the document
3
The capacity in which they signed it
4
Whose seal or stamp the document bears
5
Where the apostille was issued
6
The date it was issued
7
The authority that issued it
8
Its unique number
9
The issuing authority’s seal or stamp
10
The issuing authority’s signature

Apostille Certificate (no stamp, no signature)

Fields 2 to 4 record exactly what the Legalisation Office checked. Because every apostille shares this layout, an official in any Convention country can recognise one, even if it is written in another language.

The embassy stamp, where needed

For countries outside the Convention, there is a second layer. The destination country’s embassy adds its own stamp or sticker after the apostille. Until it does, the legalisation is not complete.

The e-Apostille

An e-Apostille is a digitally signed PDF rather than a paper certificate. You can email it and check it online. Not every document can have one. Certificates from the General Register Office, such as birth, death and marriage certificates, still need a paper apostille.

How to tell legalisation is complete

For a Convention country: the apostille alone.
For other countries: the apostille plus the embassy’s stamp.

Anyone can check that a UK apostille is genuine, using its number and date, through the GOV.UK Verify an apostille service.

Words that get confused

The same process goes by several names, and some names mean different things in different countries.

Terms	What it means
Legalisation	The whole process of authenticating a document for use abroad. Also used to refer only to the embassy step, which causes confusion.
Apostille	The certificate issued under the 1961 Convention. In the UK, the FCDO Legalisation Office issues it.
Embassy or consular legalisation	The destination country’s embassy authenticating the FCDO’s signature.
Attestation	Common in Gulf countries. It can mean the embassy step or the whole process, so ask which. In English law, it also means witnessing someone sign a document.
Authentication	A general word for confirming that a signature or seal is genuine. Some countries use it for the whole process.
Notarisation	A notary public signing and sealing a document. Often the first link in the chain, but not legalisation itself.
Certification	A solicitor or notary confirming, with their signature, that a copy is true or a document is genuine.
Public document	A document issued by an authority or an official, such as a birth certificate, court order or notarial act. The Apostille Convention applies to public documents. Private documents need a solicitor or notary first.
Competent authority	The body a country designates to issue apostilles. In the UK, that is the FCDO Legalisation Office.