There’s an old-world feel to the Best Western Charles V; its facade is accented with wrought-iron balconies, and its interiors are filled with chandeliers, ornate crown moldings, and antique furniture, including a suit of armor in the lobby. The lounge and bar area, with hardwood floors, big chandeliers, and couches and chairs covered in rose-colored fabric, has the feel of a traditional club and provides a nice, quiet place for a break after a day of sightseeing, though the decor is a bit dated. The hotel primarily attracts tourists looking for a comfortable, affordable place to stay in the heart of Madrid; most are looking more for a place to sleep than a place to hang out.

The Carlos V is located right in the center of Madrid, a two-minute walk from the renowned Puerta del Sol. The entrance is on a picturesque, pedestrian-only street, surrounded by neighborhood shops, with plenty of restaurants and bars within a few minutes' walk. Madrid’s major attractions, including the Royal Palace and the Museo Nacional del Prado, are within a 20-minute walk. There are a few different metro stops nearby; the hotel is about equidistant from Puerta del Sol and Callao stations. The Adolfo Suárez airport is about 30 minutes by car and around an hour via public transport; the hotel also runs a shuttle to the airport through the early evening.

The 67 air-conditioned rooms at the Best Western Carlos V are simple and on the small side, as is common for older European city center hotels, although some of the more recently renovated ones have polished wood floors and high ceilings. Rooms with dull grey carpeting definitely downgrade the look, and only accentuate the basic, chain-hotel-style furniture. There are Twin, Deluxe Double, and Queen rooms — twins have two beds pushed together. The mattresses might be a little firm for some guests. Bathrooms are also a tight fit, with pedestal sinks that don’t provide much space for toiletries and narrow shower/tub combos. Amenities include flat-screen TVs, minibars, safes, and hairdryers. Traffic is banned in the surrounding streets, but rooms at the front of the hotel can get pedestrian noise. Rooms on the back often look onto an air shaft. Some rooms on the front and higher floors have small balconies.

The Carlos V serves a well-stocked buffet breakfast for a small extra fee, although the variety may not be enough for longer stays. The hotel also has a classically decorated cocktail lounge, where happy hour drinks, as well as magazines, books, and games, are available for guests. There’s a small business center with two computers and Internet access, and fax and photocopying services are available. There’s public parking nearby and an airport shuttle runs from early morning to the early evening for an additional fee. The hotel's concierge is known to go out of the way to help guests with restaurant reservations and other bookings.