Traditionally, shops are open from Monday to Friday, from 9-10 am to 7 pm. Some close for lunch (1-3 pm). On Saturdays from January to November, shops generally close at 1 pm though in city centre some are open in the afternoon.
In December, shops tend to stay open on Saturday afternoons and sometimes even on Sundays for Christmas shopping. There are also many shopping centres, inside and outside the city, that are usually open every day (10-24h). In these centres, you can find the main international brands.
Find here some of the most interesting places in Porto where you can buy, eat, drink and just have fun: