The London → Mauritania route step by step
Start with whatever the underlying paper actually is. A degree certificate for a study place, a marriage record for a family matter, or a company document for a business dealing — each begins the same way, with a genuine original or a properly certified copy, never a plain photocopy.
That paper then goes to the FCDO Legalisation Office by post, since no desk anywhere handles this stamp in person. Once the office has checked the signature and returned the document, one part of the journey is done — but for Mauritania specifically, it is only the first part, not the last. A second and, for this destination, final part still lies ahead before anyone in Mauritania will rely on the paper.
Destination-specific requirements
What happens after the FCDO stamp is where this destination differs from most others on this list. Mauritania's embassy carries out its own check before the record counts as finished, and that check is not something the FCDO's process replaces or shortcuts. The exact paperwork the embassy wants for a given record type is set by the embassy itself, not published as part of the UK service.
A student presenting an academic record, or a family presenting a marriage certificate, both need this same second step regardless of how routine the underlying paper is. Skipping it and sending only the FCDO-stamped document is the single most common reason a Mauritania-bound file gets returned.
Mauritania's Hague status & what it means
Mauritania is not a Hague Convention member. That is the entire reason a second stage exists on this corridor when it does not for most of the destinations covered elsewhere on this route — without shared Convention rules, a Mauritanian office has no basis for accepting a single UK certificate as proof on its own.
It is worth being direct about this because assuming otherwise costs real time: a document sent to Mauritania carrying only the FCDO stamp, on the belief that it works everywhere the way it does for a Hague member, will not be treated as finished by a Mauritanian authority.
Apostille vs. Embassy legalisation for Mauritania
The shortcut most of this site describes — one certificate, one office, done — is not available here. Document legalisation for Mauritania keeps the older, two-authority shape: a UK check first, establishing that the underlying signature is genuine, then a Mauritanian embassy step that is the part actually recognised by Mauritanian offices.
Calling the first stage alone 'the apostille' and stopping there is the error to watch for. An apostille from United Kingdom to Mauritania, in the single-certificate sense most people mean by that phrase, simply is not the product this destination accepts; treat the FCDO step as preparation for the embassy step, not a substitute for it.
Cost & timing for this route
The FCDO leg costs £45 per document by standard post, or £40 per document on the next-day service for a registered business, with results back in up to 25 working days including postage. That figure describes only the UK stage — the check and stamp from Milton Keynes — and says nothing about what comes next in the process.
Mauritania's embassy runs on its own separate charge and its own separate timetable, neither of which the FCDO figures include, so a realistic plan treats the two legs as independent tasks rather than one combined estimate. Anyone working toward a fixed date in Mauritania — a term start, a filing deadline — should size their plan around whichever of the two legs is slower, not around the FCDO's 25 days on its own. A student aiming for the start of an academic year, for instance, gains nothing from a quick UK stage if the embassy stage that follows still has weeks left to run.