Bangkok is a city of markets and no visitor should leave without visiting several of them. The markets are generally the cheapest places to shop. This doesn't necessarily reflect on the quality of the goods sold either, and some excellent bargains are for the taking if you know where to look.
Any serious Bangkok shopping binge, however, has to start at the sprawling and sweaty Chatuchak weekend market. Wildly popular among locals and visitors alike, the market is packed each weekend with everything you could possibly need. Chatuchak is a riot and will assail the senses. Be prepared though for the heat and the crowds and bring along a bottle of water. You’ll need it.
Haggle your way through the warren of shops and set aside at least half a day, if not more, for this expedition. Fortunately, there are a few shops selling snacks, meals, ice-cream, soft drinks, and mineral water. The best time to start is 9.30am, on weekends. Take the BTS SkyTrain and hop off at the last station, Mochit. or use the underground to Kampengpet station.
The Chinatown Charoen Krung Road area is swarming with shops bursting out of every nook and cranny. This is perfect weekend browse material with everything from old transistor radios and gramaphones to gold and silk on sale. Across town, Sukhumvit Road has a street market that runs most of the day but is busiest at night. Dozens of stalls sell clothes, bags, silk items, and gifts.
Patpong night market is very popular with tourists, but I don’t recommend it. It's got the same combination of souvenirs, fake brand name items, and cheap clothes as any tourist area in the city, but prices are high. Bargaining very hard is essential to get a good deal and the touts for the go-go bars that Patpong is most famous for are annoying. Patpong is between Silom and Surawong roads, and any taxi driver will know it.
The large Banglamphu market extends over Phra Sumen Road, Chakrapong Road, and others nearby. Despite its proximity to touristy Khao San Road, this is still mainly a market frequented by locals to buy clothes, household goods, etc. There's a separate market on Khao San Road itself, which sells anything the foreign backpacker could need including backpacks, stereos, pirate CD's, books, clothes, traveling accessories, etc. Many buses stop on Ratchadamnoen Klang road, just a few minutes walk from either of these markets.
Not far away is Bo-Be market, located where Khlong Saen Saep meets Krung Kasem Road, a wholesale clothes and textiles market with cheap prices. There are a couple of amulet markets nearby also at Wat Ratchanada and Wat Mahathat.
Pak Khlong market is a very large and busy wholesale market for fresh flowers and vegetables. Many flower vendors throughout the city buy their stock here at night and sell it on the following morning. The wholesale market is mainly near the river, the cheap normal market in small streets nearby.