There are many places that you can exchange money in Bangkok. You can exchange money when you arrive Bangkok such as at the airport (worst rate) (Here is the booths that give you the better rate at Suvarnabhumi Airport). You can exchange money at the banks which have several branches in town (normal rate); it is convenient because banks have branches in the shopping malls.
But if you want a better rate, I recommend you to check the shops below. These three shops are trustable and well-known for locals. They always provide the better rate and I prefer exchanging money at these shops to the banks.
You can check the exchange rate at their websites before deciding to go to the shops. Please bear in mind that to exchange money at these shops, passport is required
K79 exchange has only one branch in Bangkok (and one more branch in Hat Yai, Songkhla Province, southern Thailand). It is located near BTS Skytrain, just a few minute walk from BTS onnut. You can check the current exchange rate, map and opening hours at its website.
SuperRich (Green) also has only one branch in Bangkok. The shop is located at Rajdamri Road, near CentralWorld. It is a little bit far from the BTS Skytrain; it would take around 15-minute walk from Chit Lom BTS Station. You can check the current exchange rate, map and opening hours at its website.
SuperRich (Orange) currently has 10 branches in Bangkok, and 1 branch in Khonkaen. Each branch offers different rate. Some branches buy foreign currencies only (does not sell). So, it is good to check the current exchange rate, map and opening hours of each branch at its website before going there.
Yenjit Exchange has several branches in Pattaya, and a branch in Bangkok. The rates are different between Pattaya and Bangkok. For Bangkok branch, it is located at Paseo Ladkrabang (near Suvanabhum airport). You can check the current exchange rate, map and opening hours at its website.
So, just choose the one that is not far from you and provides the best rate. Happy traveling Thailand!
Have you ever exchanged money at these shops? Share your experience with me in the comment!