The oath belongs to the translator
Start with the one point people get wrong. A certified translation of a Translator's Affidavit in Brighton is sworn by the translator, not by you. The declaration names the source language, names the target language, and states that nothing was left out or added. It is written in the first person and dated, and it stays bound to the pages it describes.
The witness and the seal
The oath then has to be taken in front of someone. A solicitor or a notary public watches the translator sign, checks who they are, and marks the page with a seal and a date. That witness is drawn from the England and Wales roll, and nothing obliges them to sit in Brighton. Their part is short, but without it the page is only a private note.
What that seal actually proves
A seal proves an event, not a standard. It records that a named person, identified on the day, signed this page in front of the witness. It makes no claim about grammar, register or wording. Accuracy rides entirely on the translator's own oath. Put the two together and you have an official translation of a Translator's Affidavit in Brighton that a receiving desk can act on.
Getting the source record in Brighton and Hove
Where the sworn text rests on a civil record, start with a fresh certified copy. Brighton & Hove Register Office at the Town Hall, Bartholomew Square, Brighton BN1 1JA covers both towns from one desk, so a Hove birth and a Brighton marriage are ordered from the same place. Your own certificate then never has to leave the house.
Read the same way nationwide
Nothing here is local custom. A certified translation of a Translator's Affidavit in United Kingdom practice comes down to the translator's signed statement of accuracy plus a witnessed signature. UKVI and the General Register Office weigh a bundle sworn on the south coast exactly as they weigh one sworn anywhere else in the country.