Will a fan really keep me cool?

In Bangkok's humidity, a fan won't lower the temperature, but it will evaporate the sweat on your skin, which is your body's primary way of cooling down. Position it to hit your pulse points.

Can I survive without AC entirely?

Yes, if you choose accommodation with high ceilings and river-facing windows. Avoid concrete 'shoebox' rooms on the top floor of buildings, as they trap heat all day.

Staying Cool in Bangkok Without Air Conditioning

Stay cool by utilizing the 'cool hours' for activity, seeking out high-ceiling traditional architecture, and using water-based cooling techniques. Carry a small hand fan and stay hydrated with electrolytes to manage the 32°C (90°F) average daily heat.

Sync your schedule with the heat. Be outside only from 6:00 AM to 10:00 AM and after 6:00 PM. Between 12:00 PM and 3:00 PM, stay in buildings with high ceilings, marble floors, or heavy fans, which dissipate heat better than modern concrete boxes.
Master the 'Thai Shower'. Take frequent cold showers throughout the day. Don't dry off completely; leave a light layer of water on your skin to create a cooling effect through evaporation as you stand under a ceiling fan.
Use a 'Khang' (Cooling Powder). Buy Prickly Heat cooling powder (Snake Brand) at any 7-Eleven. Apply it after your shower. The menthol creates a sustained cooling sensation on your skin that lasts for 30–60 minutes even in stagnant air.
Strategic cross-ventilation. If your room has two windows, open both to create a breeze. If only one window exists, place a fan in the window frame facing inward at night, but during the day, close all windows and curtains to trap the cooler morning air inside.

Will a fan really keep me cool?: In Bangkok's humidity, a fan won't lower the temperature, but it will evaporate the sweat on your skin, which is your body's primary way of cooling down. Position it to hit your pulse points.
Can I survive without AC entirely?: Yes, if you choose accommodation with high ceilings and river-facing windows. Avoid concrete 'shoebox' rooms on the top floor of buildings, as they trap heat all day.