The sexy, adult-only Beloved Playa Mujeres is a rare breed. It's a true boutique hotel, with just 109 rooms and personalized service, which includes a check-in cocktail, cool towel, and pillow menu. But it's also an all-inclusive resort -- though if all meals and drinks (including top-shelf liquor) weren't included, you'd hardly know it. There are no tacky wristbands, no early-morning hustle for lounge chairs, and no reservations required for the restaurants (all a la carte and excellent). Included activities, such as guided ocean kayaking and bike tours, are better than the norm. Starting at 960 square feet, the huge, all-white rooms have decadent bathrooms and private balconies -- many with ocean views and some with plunge pools. Room service is available 24/7. The gorgeous 35,000-square-foot spa has an impressive hydrotherapy circuit and the three chic outdoor pools feature whirlpools and food and drink service.

Casa Velas inhabits a Puerto Vallarta neighborhood that feel like Beverly Hills. The luxurious adult-only hotel has perfectly manicured grounds (encircled by a golf course), tennis courts, a botanical garden, and a large freeform pool with swim-up bar and built-in tiled seating. Its elegant restaurant serves Mexican and American cuisine three meals a day and its nearby exclusive beach club -- accessed via the hotel's free shuttle -- has a sushi bar restaurant and infinity pool overlooking the beach. Decorated in a tasteful, residential Mexican style, the 80 rooms are all spacious and upscale, with excellent mattresses, pillow menus, marble bathrooms, free minibars, and 24-hour room service.

Located in a private community in Manzanillo, Pepes Hideaway is a relaxing, peaceful oasis. Each one of the six bungalows has a gorgeous thatched roof, furnished balcony with a hammock (and free coffee or tea delivered in the mornings), stocked mini-fridge, bathrobes, and free Wi-Fi. The rooms lack TV and air-conditioning and mosquitos can be a problem, but fans, bug spray, and citronella candles are provided. Three delicious meals are prepared each day -- large traditional breakfasts, casual lunches served by the pool or brought to guests at the beach, and three-course dinners typically starring seafood. Beer, wine, cocktails, and non-alcoholic drinks are available 24/7. The on-site pool has an adjacent whirlpool built onto the edge of a cliff, and the private beach is a 10-minute walk away, though the staff will also drive guests there (personal attention from the staff is a big plus; they will fulfill most requests). Kids are rarely present, making Pepes a wonderful retreat for couples.

Verana is an adult-only boutique resort nestled in a hillside high atop the bay of Yelapa, a small village on the coast of Mexico that is only reachable by boat. Forty-five minutes south of Puerto Vallarta, Verana offers eight uniquely designed, rustic houses that include completely open-air, gazebo-style rooms perched out over the jungle; some have private pools. While facilities are minimal and not exactly upscale, this secluded jungle experience -- which includes a lovely restaurant, spa, and infinity pool -- is popular among couples looking to get away from it all. Due to the isolated location, though, it takes some effort to explore Yelapa beyond the property.

Right off the beach in a secluded area 15 minutes north of Playa del Carmen’s center, the 23-room Le Reve Hotel & Spa has an instantly relaxing vibe well-suited to couples and honeymooners. The boutique hotel's interiors are upscale and stylish after a 2014 makeover. Rooms have lots of special elements ranging from hand-painted tiles to plunge pools to evening turndown service, though dim lighting can be a downside -- as can the price of cabs to and from Playa proper. However, positive features include the (unsupervised) kids' club, pool bar, massage area, classy sports bar, impressive gourmet restaurant menu, and free cooking classes. Note that select premium wines and spirits aren't included in the all-inclusive plan.

Opened in September of 2015, the upscale Live Aqua Boutique Resort is a hip, adult-only hotel in downtown Playa del Carmen, situated right on the lively Fifth Avenue that's lined with dining, drinking, and shopping options. Its 60 rooms are spacious and feature minimalist modern decor, private balconies or terraces, and sleek bathrooms with large walk-in rainfall showers -- plus Master Suites have outdoor whirlpool tubs. The hotel has an expansive rooftop terrace with an infinity pool and panoramic views over the coast and city, as well as several on-site dining options. Other facilities include a small spa and fitness room.

Open only to guests ages 16 and older, Villa Premiere offers the best of two Puerto Vallarta worlds: it’s both a beachfront all-inclusive and an urban boutique. One of the few beaches near town -- Playa Camarones -- is directly in front of the hotel, and downtown Puerto Vallarta is just seven blocks away. With both European and all-inclusive plans for its 80 rooms, there’s room for multiple budgets. In 2015, the hotel also renovated all of the rooms and some of the interior. While the beach isn’t necessarily anything to write home about, the combination of amenities packed into the compact space -- gym, spa, pool, restaurants, 24-hour room service -- are the same as what you will find at any of the mega resorts in town.

This 62-room couples-only boutique hotel is located on a white-sand beach in the southern part of Isla Mujeres. It features all the standards of larger resorts -- a nice pool with a swim-up bar, 24-hour room service, balconies with ocean views -- but on a smaller scale and with a more intimate vibe. Airy rooms are luxurious and elegant with jetted tubs for two, flat-screen TVs, and free Wi-Fi. The open-air restaurant has a revolving menu that is a little limited. Hotel perks include a lack of crowds -- no fighting for pool chairs here -- along with a fitness center, small spa, and quiet beach with non-motorized water sports.

This 94-room, adult-only hotel is about a 10-minute drive away from Tulum town. It has a dual-level infinity pool area with swim-up bar and hot tub section, and its large beach has both soft sand and a rugged, rocky coastline (swimming is not recommended). The food and yoga classes get mixed reviews and many public spaces around the resort feel neglected. Room air-conditioning, 24-hour electricity, a fitness center, personal jetted tubs, and TVs are nice perks for the area.