Hotel request for full name, sex & date of birth. Legit?

Did you book directly with the hotel, or through booking.com? Was the number you called the same number that is on the hotel,website?

I did notice a different phone number in yesterday's email, but called the hotel website listed phone number. The sender of the email answered! That was reassuring.

Booked directly

The Italian govt. requires hotels etc to record the identifying info for all guests. Some request the info in advance to save time. Others require you to show passports during the check in process so they can get the same info.

The hotel would have probably asked you for your passport at check in and made a photocopy, which would have the information they are requesting ahead of time. It's a legal requirement in Italy to record information about guests and register it.

Thank you! You have helped alleviate my concerns.

Italian law dating back to the Mussolini's regime but modified and promulgated over and over again since, requires that operators of hotels, B&B, vacation homes, hostels, campgrounds etc. register their guests, make a copy of their ID, and communicate the information card to the Questura (Provincial police headquarters) within 24 hours from check in.
The police website card they submit to the police must have the following information for the single guest or for the head of the group or the head of the family:

1. Date of arrival
2. Number of days staying in the premises
3. Last Name
4. First Name
5. Sex
6. Date of Birth
7. Place of Birth
8. Citizenship
9. Type of Identity Document
10. Identity Document number
11. Date and Place of Issuance of Identity Document

For the rest of the members of the same group/family it is sufficient to transmit items 3, 4, 5, 6, 7, 8.

Your hotel may have requested this to start filling the info. But sooner or later, on or before the date of check in, they need the info above.

Thank you for the detailed explanation. I guess the request just took me by surprise, in that none of our other reservations had requested this information.

In France they also take away your passports (briefly) upon checkin and then return them

This hotel is on top of things. The others will get the information from you when you check in.

In the past we have sent photos of our passports directly to the lodging.

We spent a month in Italy a few years ago and were never asked for this, although we were asked to show passports on checking in.

I have two Italian hotels booked for September and so far haven't been asked either.

I don't think I would be sending that information over email.