A certified translation for a UK visa application is a translation accompanied by a signed statement of accuracy confirming it is a true and complete rendering of the original document, together with the translator's credentials, contact details and the date. UKVI does not require notarisation.
If a document isn't in English or Welsh, UKVI needs a certified translation alongside it — spouse visas, student visas, Skilled Worker, settlement, ILR. Same rule, every category. The Home Office's published guidance, *Specified evidence: documents in a foreign language* on gov.uk, sets the requirement out in one short list.
What trips people up is the gap between UK and US rules. American immigration (USCIS) routinely requires notarisation, so applicants who've been through the US process — or read US-based forum advice — assume the UK is the same. It isn't. Paying £30–£50 per document for a notary adds nothing UKVI is looking for. For the full UK visa translation requirements, see our visa guides.