The walking street campaign to encourage more spending and boost tourism will start on Sunday in Bangkok before expanding to all provinces the following week.
Pedestrians will have Silom and Yaowarat roads to themselves on Sunday and other provinces will follow with similar events on Dec 22, government spokeswoman Narumon Pinyosinwat said on Friday.
After Sunday's event, Yaowarat Road will be closed for pedestrians every Friday, Saturday and Sunday from 7pm to midnight.
Silom Road will go car-free on the third Sunday of the month from noon to 10pm, while Khao San Road will be wide open to pedestrians every Monday from 5pm to midnight.
In the provinces, organisers of walking streets will be required to offer locally made products among the items available for shoppers. Several provinces already have walking streets to add to their visitor appeal.