Park Hyatt

Where: Penthouse Bar + Grill (35/F) 
What: Once you’ve had your fill of discount drinks on the 10th floor, head on up to the 35th, where Penthouse Bar offers a range of price drops between 6-9pm: prosecco falls from B420 to B250, Asahi from B170 to B140, plus snacks including chicken wings from B340 to B240 and Wagyu beef sliders from B490 to B340. 
Central Embassy, 88 Wireless Rd; 02-012-1234. Open daily midday-2:30pm; 5:30pm-midnight

Okura Prestige

Bangkok Marriott Hotel The Surawongse

Where: Yao Rooftop Bar
What: Yao’s cocktails range from the affordable Shanghai Mule (B222) to the pricier French 78 (B688)—so pick wisely.
32/F, 262 Surawong Rd., 02-088-5666. Open daily 11am-2:30pm; 6-10:30pm

Marriott Marquis Queen’s Park

Where: Goji Terrace (L/F)
What: If you arrive too early for Lobby Lounge, just shimmy on over to Goji Terrace, where you can get 50-percent off your first beer from 5-8pm daily, including classics like Chang and Heineken and a variety of draft beers. They also stock Maisel’s Weisse, La Chouffe and BrewDog here, and serve a range of seafood and grilled meats. Visit Friday-Sunday 6-9pm for live music. 
199 Sukhumvit Soi 22, 02-059-5555. Open daily 6am-midnight

Centara at CentralWorld

Where: Red Sky Bar (55/F)
What: Red Sky Bar not only offers one of the best views in Bangkok but also buy-one-get-one-free on drinks and snacks between 4-6pm daily. There’s a wide range of food on offer, from cold appetizers to warm desserts, alongside drinks including sparkling wine and Champagne. 
999/99 Rama 1 Rd., 02-100-1234. Open daily 4pm-1am

Anantara Siam

InterContinental

Where: Theo Mio Italian Kitchen (G/F)
What: From 5-7pm, Mon to Friday, Italian wines, local beers, and the likes of their Hugo, bellini and negroni cocktails are all available at a discounted rate, starting from B100—perfect for afterwork drinks (you might even be able to afford a round!).
973 Phloen Chit Rd., 02-656-0444. Open daily 11:30am-11:30pm

Mandarin Oriental Hotel

Where: Bamboo Bar (G/F)
What: Every day from 6-8pm, Bamboo Bar holds their “Aperitif Time,” when drinks like their mojito, negroni, margarita, Thai Daiquiri (coconut and pandan vodka with fresh lime and sugar) and more are discounted from B490 to B290. Their tasty, Thai-inspired signature drinks are also available for under B450.
48 Oriental Avenue, 02-659-9000. Open Mon-Thur 5pm-1am; Fri-Sun 5pm-2am

Grand Hyatt

Where: BAR@494 (L/F)
What: Grand Hyatt provides various offers throughout the week. On Tue, ladies can pay B599 for unlimited sparkling wine between 7-9pm. From Wed-Mon, 7-9pm, you can pay B799 for their free-flow “Wine Buffet,” as selected by their sommelier. Finally, their happy hour offers two for one on selected wines and beers between 5-7pm Mon-Sat and from 3-11pm on Sun. 
494 Ratchadamri Rd., 02-254-1234. Open daily 3pm-midnight

Hotel Indigo 

The Athenee Hotel