El Salvador reads Spanish
Salvadoran offices work in Spanish, and a British record waits until a Spanish version arrives with it. A certified translation into Spanish in Birmingham creates that version from a scan and leaves your English sheet exactly as it was issued, in your hands and unmarked.
The interesting question is not how the Spanish gets written. It is why so many files come back anyway, having been translated perfectly well. In practice the causes are few, they repeat, and nearly all of them are decided before anybody starts translating. Four of them account for most of the wasted rounds, and each has a fix that costs nothing.
Two faults in the source material
The first is an unscanned page, usually a reverse side that appeared empty. The second is a seal that arrives too dark, too cropped or too small to read. Both are faults of capture rather than translation, and both are cured with a flat surface, good light and the patience to turn every sheet over.
Neither can be repaired later by a translator. An official Spanish translation in Birmingham can only describe what it can see, and where a mark is unreadable the honest entry is that it is unreadable. That entry survives inspection; an invented reading does not.
Two faults in the bundle
The third fault is inconsistency: one person spelled several ways across documents translated at different times. A reader cannot resolve that, and will not guess. Sending everything as a single batch lets one translator fix each name, place and institution once and carry that decision across every sheet in the set.
The fourth is the missing signature. Fluent Spanish with nothing beneath it is not certified, and no amount of quality in the prose changes that. A qualified translator's certificate of accuracy, naming them and dating the work, is the element that makes the page usable at a counter.
Rate, clock and the spare copy
Pricing is per side at about £25 a page, and delivery is 2–3 business days as standard or 24 hours in express. A sworn Spanish translator in Birmingham is not part of the picture here, because El Salvador takes the certified form and a courtroom oath adds nothing to it.
Where a civil record sits in the bundle, Birmingham Register Office on Holliday Street issues fresh certified copies of births, marriages and deaths for an official fee. A new copy scans better than an old one, which quietly removes two of the four faults before you have translated a word.