Riva Arun 

Hidden in the same soi as Blue Whale cafe, this boutique hotel boasts a charming colonial-style design from Soda Thailand. The 25-room Riva Arun is located close to landmarks like the Grand Palace and Wat Pho and faces the majestic Wat Arun along the Chao Phraya River. While almost every single room comes with a great view of the temples and old buildings in the Tha Tien community, the contemporary suites are equipped with outdoor Jacuzzis facing Wat Arun. Rates start at B2,990/night for the Riva Arun Studio. 
392/25-26 Maharaj Rd., 02-221-1188. www.snhotels.com/snc/rivaarun 

Chann Boutique

Hidden in the small alleys by Bangkok Noi canal, Chann features Thai-style architecture that pays homage to the surrounding riverside community, dating back to the Ayutthaya and Thonburi eras. The hotel is made up of two-story wooden houses, featuring 18 rooms and four special suites that range in size from 30-45 sq meters. Rates start at B4,599 right now for non-river-view rooms, but they also have special rates for Thai residents available from now through Oct 31 when you use the promo code THRES on www.channbangkoknoi.com
30/1 Wat Dusitaram, Somdej Phra Pin Klao Rd., 02-435-5997

Raweekanlaya Bangkok

Originally built in the late 1800s as the residence of King Rama 6, this boutique hotel features 38 rooms, each inspired by a poem from Thai literature. There is also an on-site Imperial Spa that offers traditional Thai massages, a swimming pool featuring four comfy sunbeds, and a pool bar that serves up healthy juices. Its restaurant, Raweekanlaya Dining (see page 4), uses organically-sourced produce and features garden where guests can pick their own ingredients. Rates start from B2,600/night. If you book 15 days in advance, you’ll also get an extra 35 percent discount on your room, and receive complimentary breakfast. 
164-172 Krung Kasem Rd., 02-628-5999

SSIP Boutique Dhevej Bangkok        

This 1920s colonial-style mansion is one of the few remaining Thai residences on Phitsanulok Road, nor far from the Dusit Palace. That also means that the 19-room boutique hotel features antique four-poster beds, dining tables, chairs and utensils. The breakfast includes royal Thai cuisine that uses vegetables freshly picked from the on-site organic farm. Rates start from B2,200/night.
42 Phitsanulok Rd., 02-228-2899. www.ssiphotelthailand.com