The apostille is added to a document to ‘legalise’ the document for use in another country.

If you have a UK document that you need to use outside of the UK, you may have been asked to get the apostille. Adding an apostille to a document enables the overseas authority to check that the signature or seal on your document has been checked by the UK government (the FCDO Legalisation Office).

The Legalisation Office keep a register of signatures and seals commonly added to documents. When they have checked a documents seal or signature, they add the apostille certificate to the back of the document. Anyone overseas can then use the FCDO website to verify the apostille number on the document.