We spend two night at this hotel and it was wonderful.
Rooms are big, very clean, has WiFi in the rooms.
The breakfast was very good as well as the dinner we had on the second night.
The staff was very helpful.
It is a place to be recommended.

I'm extremely critical in my reviews as Tripadvisor has served me abounds for the past decade and I try to pay it forward. A solid 4.5 stars for the reasons below, I would stay here again when in Olbia.
For starters I stayed in the #1 hotel of downtown Olbia called Panorama last year (read my review) not pleased with it most notably the bed comfort amongst a range of issues. That turned out to be the main reason for choosing the Hilton as many will attest the beds in Italy can be difficult. I'm not particularly a "chain hotel" kind of traveler, although in the past year a few stays at Springhill Suites line has changed my mind and given my faith corporations can listen to the customer.

Pros; Helpful breakfast Staff (Pietro notably), beautiful property and in my opinion an excellent location last years "downtown hotel" was difficult to find, and parking was a large issue a couple of nights in their lot. There is plenty of parking at the Hilton Olbia, even at full capacity. I really like to see the American chain booked solid it presses the local boutique hotels to constantly raise the bar making it better for all potential customers. I had trouble finding a great deal of fault at the Hilton. Very comfortable bed with 4 comfortable pillows as it should be, large bathroom, room in the minibar for your own items, large balcony, TV channels in English, the maid came even when we woke up at 3pm without us even having to ask. Balcony was a plus just wish I had a view of something other than my car.

Needed Improvements; The bathroom door threshold that randomly juts up 1.5” has to be removed, put a 3" wide marble threshold down as is the norm everywhere in the world immediately. Someone is going to break their toe or fall face first in the middle of the night with that strip of stone you have now, that would never be allowed in the US its a safety issue and dangerous. Internet was intermittent, slow and spotty at best (found it worked well only on my balcony) absolutely unacceptable for a nearly brand new hotel and American chain, I will attribute it to the hotel being at full capacity but I'm taking half a star off my rating because of it. Wifi worked great in lobby. Hotel staff needs to speak english, at least 1 person at the front desk at all times. The young guy came off as unhelpful mostly because of his lack of English giving you the usual nod that he understands you but he really doesn’t, and the girl next to him upon check in spoke just as little. I had a long flight I don’t need to be using sign language or repeating myself at an American hotel chain after being up since 6am for basic questions about the room, internet connectivity, check out time and parking. I see A LOT of complaints on here about the staff across the board, maybe Hilton needs to clean house on this one? I personally can’t attest too much of it because my interaction was very minimal other than the front desk and breakfast staff.

Suggestion; Get rid of the small gym on top floor or whatever that locked room is and maybe set up a happy hour to watch the Sunset? You have sunset based bars charging an arm and a leg to watch what is truly a Sardinian gem their sunsets nightly.

Overall; I would definitely and will most likely return to the Hilton in Sardinia as we truly enjoy this island and the property checked all the right boxes at a fair price even during peak season (wish I could say the same for the airlines). Its proximity allows easy access with a rental car to Porto Cervo & south to San Teodoro and all the wonderful beaches in between. If you decide to instead stay "downtown" take into account cruise ship passenger traffic throughout the day and evening, closing of streets like Corso Umberto for pedestrians and limited parking especially in the evening, none of those issues can be found at the Hilton and you get a comfortable bed at the end of the day.

From the very start when the taxi picked us up we were made too feel welcome. The hotel is very clean and the rooms are quite spacious and well equipped. We ate in the restaurant a few times and the selection is very good and the food of excellent quality. The breakfast is more than sufficient and if asked the staff are more than willing to provide what you require (fried eggs etc.) The hotel is slightly out of town but we felt that this just added to the holiday the short walk was just the job. The hotel bar is a good place for pre and after dinner drinks. All of the staff were very pleasant and nothing was too much trouble.