Most Vietnamese are early risers, so businesses and shops open early. Government offices are open from Monday through Friday from 7:30am to 4:30pm. Most businesses are open Monday through Saturday from 8:00 am to 5:00 pm

Banks are open Monday to Friday from 8:00 am to 3:30 pm and on Saturdays from 8:00 am to 1:00 pm. Lunch time is usually between 11:30 am to 1:30 pm.

Many businesses, shops, and all government offices are closed during this lunch period. Shops are open from about 8:00 am to 9:00 pm, with some open longer.

Source: www.ecotravelvietnam.com