Why this sheet is the one asked for
Most papers that carry a mark abroad describe an event: a birth, a marriage, a qualification. This one describes a change. Knowing how to apostille a Certificate of Naturalization begins with knowing why it is asked for at all — it states the holder's present citizenship, where an earlier record from another country states only where they began.
That gives the document an unusual place inside a file. It is often the piece that ties the other papers together, because the name and the standing it records are what the rest of the file has to agree with. Settling that agreement before anything is posted costs nothing; finding a mismatch afterwards costs a whole round trip.
One office, wherever the certificate came from
To apostille a Certificate of Naturalization in the United Kingdom is to deal with one office. The Legalisation Office (Foreign, Commonwealth & Development Office) covers the whole country from PO Box 6255, Milton Keynes MK10 1XX. It works by post in both directions and keeps no counter, so the Brighton end of this job is a desk and an envelope rather than a visit.
Papers of this kind rarely travel alone. Where a marriage entry or a child's birth entry goes along with it, Brighton & Hove Register Office at Town Hall, Bartholomew Square, Brighton BN1 1JA issues fresh certified copies of those records, so the originals stay with you.
What it costs, and what is not published
The apostille cost for a Certificate of Naturalization in Brighton is the national charge: £45 per document by standard post, or £40 per document next-day where the sender is a registered business. The unit is the sheet, so a file of three papers is charged three times over.
No turnaround is published, so no date belongs on this page. The office works through the mail in both directions and keeps no public count of days. What remains yours is everything that happens before the envelope goes: the copies you gather, the spellings you settle, and the day you choose to start.
What the mark claims here
The legalisation of a Certificate of Naturalization in Brighton ends in a certificate attached to that one sheet. It speaks to the signature and the seal, not to the decision behind them, and it says nothing about the holder beyond what the paper already carries. That is enough for a reader abroad, who otherwise has no way of placing a British signature.
Whether a translation is wanted is decided at the far end and varies from one country to the next. The mark itself changes nothing about the wording: it goes onto the sheet as issued, so it neither produces a version in another language nor calls for one to be made.