The St. Regis San Francisco Rating: 5.0 Pearls
The city's top luxury hotel is hard to beat for a romantic retreat. The spacious and modern rooms are among San Francisco's best. A touch-screen next to the bed controls the music, lights, shades, and TV --- and puts guests in contact with a 24-hour butler, who will, among other things, draw a bath in the deep tub that opens to the room (try the Rose Petal Romance bath). Downstairs, Ame restaurant is a dining destination in its own right, and Remede Spa serves chocolate truffles and champagne in its relaxation rooms.
Fairmont Heritage Place, Ghirardelli Square Rating: 4.5 Pearls
Opened in 2008, the Fairmont is a polished new gem in an old landmark -- a former chocolate factory built in 1893. The outdoor terrace overlooking San Francisco Bay has two fireplaces. Every one of the top-of-the-line units, all one- to three-bedroom apartments, has a fireplace, luxurious bathroom, and super comfortable beds (some with bay views). In Ghirardelli Square, you can go to a free wine tasting, wander along waterfront paths, or dine at a restaurant with a view. Want to go further afield? Let the hotel's free Maserati Quattroporte car service take you. Sweet.
The Huntington Hotel Rating: 4.0 Pearls
Nob Hill, San Francisco's swankiest neighborhood, is home to many of its grandest hotels -- stately old buildings with cavernous marble-filled lobbies and hundreds of rooms. By contrast, the elegant 136-room Huntington Hotel is more intimate and unassuming. Yet it's just as luxurious as its neighbors. The spacious, newly renovated rooms overlook either the city or quiet Huntington Park across the street. The formal staff is attentive, yet discreet. The hotel's Nob Hill Spa is one of the city's best, and guests can use its indoor pool and lounge with a fireplace for free.
Hotel Palomar Rating: 3.5 Pearls
Even though the Palomar is smack in the middle of Market Street's big-box retailers, this cozy downtown hotel has the feel of a mod art gallery. In keeping with the hotel's "Art in Motion" theme, paintings from local museums line the walls of the dimly lit lobby. The Fifth Floor restaurant, which offers a New American menu and an extensive wine list, is home to a free nightly wine tasting. And the large, modern rooms include fun touches like animal-print bathrobes.
Mandarin Oriental, San Francisco Rating: 4.5 Pearls
If ever there was a hotel room designed to stay in all day and night, this is it. From the top 11 floors of San Francisco's third-tallest building, couples can soak in breathtaking views of the city and bay. The spacious rooms -- renovated in 2012 along with most public spaces -- are distinguished by their subtle Asian-inspired design and luxury details like featherbeds and marble bathrooms with large tubs. The astounding service includes free afternoon tea in the room and 24-hour room service. You'll barely notice you're staying in the less-than-romantic Financial District.
Hotel Vitale Rating: 4.0 Pearls
California hotel chain Joie de Vivre knows how to do charming boutiques, and this stylish hotel on the Embarcadero waterfront is no exception. The hotel's Spa Vitale is a standout and offers the Bathing Ritual: Couples soak in twin tubs in the private rooftop bamboo garden. Spacious and tranquil guest rooms have swanky bathrooms, and most have terrific views of the bay and Bay Bridge.
Clift Rating: 4.0 Pearls
Couples looking for a hip scene and sexy ambiance will find it at this trendy hotel. The cavernous Philippe-Starck-designed lobby is selectively lit to highlight the funky furniture. Crowds flock to the dimly-lit Redwood Room bar, paneled in warm redwood and dotted with velvety red sofas and chairs. Next door, Asia de Cuba restaurant serves its acclaimed Asian-Latin fusion fare. Rooms are on the small side, but the minimalist design and white and lavender décor make them feel larger than they are.
Hotel Rex Rating: 3.5 Pearls
For an affordable urban getaway, consider this quirky Union Square boutique, themed after 1920s and '30s literary salons. Its lobby is filled with antique books and armchairs fit for an afternoon poring over the classics. A great lobby bar hosts a free nightly wine hour. The bistro-style Library Bar serves reasonably priced Californian fare in a charming dining room. The rooms, while small, are surprisingly modern, and the pillow-top beds are plush and comfortable. And from this downtown neighborhood, it's easy to jump on a cable car and explore the city.