I may be going to Thailand later this year and would love to know where to go for great shopping. The only thing that doesn't really interest me would be higher-end shops like Chanel, etc. that can easily be found in the U.S. I like small, independently run boutiques or just areas with interesting stores. That said, I'd be interested in department stores as well.
So much shopping to be done in Bangkok that I feel like I've only barely scratched the surface even though I've been to a bunch! Here are the standout few:
For Thai mall shopping experience, check out these two places. Both are really nice and filled with Thai department stores, independent stores, and lots of restaurants:
For the night street market experience, check out these places, which are all the classier and more legit night markets (not red light district):
Shop your heart out! ;D
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Also check out the Chatuchak Weekend Market. Known as J.J. (part of the JJ Mall), over 5000 stalls of everything imaginable including your own live animal. Try to pack that.
If you can get down to Bang Lamung, be sure to check out the Floating Market. Everything is sold from boats. It's really beautiful around dusk.