Who stamps a citizenship record
A paper that records your citizenship in Italy counts here as an administrative act, so the state office handles it. To apostille a Certificate of Naturalization in Italy you deal with the Prefettura, the branch of the state that sits in each provincial capital. The apostille it adds is a single sheet that vouches for the signature below, and nothing more. It does not judge whether your file is complete, whether the wording suits the country you are writing to, or whether a translation is wanted.
Getting the copy right
Work out which body holds your record and ask that body for a fresh certified copy. Do not send a scan, a screenshot or a copy you ran off yourself, because none of them carries a live signature. Anyone asking how to apostille a Certificate of Naturalization should treat this as step zero, since the state office can only vouch for a signature it holds on file. Read the sheet before you leave the counter and check the seal, the date and the officer's printed name.
What the state charges
Money on this route is simple and fixed. The apostille cost for a Certificate of Naturalization in Bologna comes down to a €16 tax stamp for the document. Buy it and fix it to the paper before you hand anything in. Some papers are let off that charge, so put the question to the office first rather than buying blind. Each document in a bundle carries its own stamp, so a file of four papers is four stamps, not one.
When the court route applies instead
There is a second counter in the city and sending a file to the wrong one wastes a trip. Judicial and notarial acts belong to the Procura della Repubblica, the office attached to the court, while ordinary state records belong to the Prefettura. If a notary drew up the copy you hold, or a court issued it, the Procura is your counter. Read the top of your sheet and see whose signature closes it before you plan the journey.
Sending the bundle onward
After you apostille a Certificate of Naturalization in Bologna, treat the result as one object. Italy has issued this stamp under the 1961 Hague Convention since 1978, and the stamp is designed to be read across borders without a further visit. Even so, the desk abroad sets its own rules on age of copy, form and language, so put your question to it in writing first. Do not unpin sheets, re-scan the bundle or fold it into an envelope that crushes the seal.
Mistakes that cost weeks
Three problems account for most delays in the legalisation of a Certificate of Naturalization in Bologna. The first is a stale copy, released months ago, which some foreign desks refuse outright. The second is a name or birth date that reads one way on the record and another way in your passport. The third is a translation ordered before anyone confirmed which language the reader wants. Each of those is cheap to fix now and slow to fix from abroad.