Apostille for a Consent Letter: FCDO Legalisation Guide

A consent letter is written permission — for example, permission from a parent for a child to travel with another adult, or consent from one party for another party to sign or act on their behalf. When the letter must be used outside the United Kingdom, the receiving border guard, court, bank or government office has no way to check the signature by itself, so it asks for an apostille confirming the document is genuine. The FCDO Legalisation Office issues that apostille. This article describes the working route: certification first, then the right kind of apostille, with official fees and timings.

The certification step comes first

A consent letter is a private document: the Legalisation Office does not keep a register of consents it can check the letter against. Official guidance gives the route for such documents — they can be legalised when certified by a UK public official such as a UK notary or solicitor. Signing the letter before a UK notary, or having a solicitor certify the signature, is therefore the first step; that certified signature is what the office will verify and the apostille will attest.

The same guidance advises checking with the request side whether the original document or a certified copy is needed, and whether it must be signed by a particular person such as a UK notary or solicitor — for a consent letter this often decides acceptance, so ask before notarising.

Paper apostille or e-Apostille

Two apostille types exist. For a consent letter both are normally possible:

• Paper-based: the notarised letter is posted to the Legalisation Office, which verifies the notary’s or solicitor’s signature, attaches the stamped apostille certificate and returns the document. The standard service usually takes up to 25 working days, plus courier or postage time.
• e-Apostille: the letter is uploaded as a PDF electronically signed by a UK notary or solicitor, and the result comes back by email — the office processes this in up to 2 working days.

The electronic route requires a real qualified electronic signature from the notary on the PDF; a scan of a hand-signed letter does not qualify for it. If the receiving authority wants the physical letter, use the paper route.

What it costs

Each document legalised carries a fee. The official rates: £45 per document for the standard paper-based apostille, plus courier or postage costs; £35 per document for an e-Apostille. Faster paper services exist for registered businesses. If the document cannot be legalised, the fee is not refunded — which is why it matters to check the notarisation and the recipient’s requirements before you apply. Courier return costs are additional on the paper route (from £6 per 1.5kg for UK addresses), and couriers currently cannot return legalised documents to certain restricted destinations — so plan a different return address or an electronic route where the recipient accepts it.

The process, step by step

1. Agree the wording requirements with the recipient, including the language details of the letter — e.g. the child’s details, dates, destinations or the consent actions.
2. Sign the letter before a UK notary or have it certified by a UK solicitor — or prepare the electronically signed PDF for the e-Apostille.
3. Apply online for the chosen apostille type and pay the per-document fee.
4. On the paper route, post the letter to the Legalisation Office and give a return address; on the electronic route, upload the signed PDF.
5. The office verifies the notarisation and attaches the apostille; the recipient can then check the apostille online to confirm it was really issued by the office.

What to confirm before applying

• Whether the receiving country accepts an apostille (countries within the Hague Convention) or requires attestation at its own embassy.
• Whether a certified translation must travel with the apostilled letter, and who is expected to provide it.
• Whether the receiving authority requires the original letter — that decides between the paper and electronic routes.

Summary

A UK consent letter is apostilled after certification by a UK notary or solicitor, which is what the FCDO Legalisation Office verifies before attaching the apostille. Choose between the paper route — the standard service, £45 per document plus courier or postage costs, usually up to 25 working days — and the e-Apostille — up to 2 working days, £35, on a PDF electronically signed by the notary. Ask the recipient for its requirements first, and check the courier limits if the letter must travel to a destination with restricted postal services.

Apostilla UK editorial team · checked 31 October 2026