Though hours vary, most banks are open weekdays from 8 am to 5 pm. Private currency exchange offices usually have longer hours, and some are open all night.
Gas stations on the main roads are open 24 hours a day.
In season (from May through September), most museums, castles, and other major sights are open daily—except Monday—from about 9 am to 4 pm. Hours vary at other times during the year, and some attractions in smaller, off-the-beaten-track places shut down altogether from November to March.
Most pharmacies are open weekdays from about 9 am to 6 pm, and are closed weekends. For emergencies, some pharmacies maintain weekend hours, though these can change from week to week. Ask someone locally for advice.
Most stores are open weekdays from 9 am to 6 pm, but a growing number now are open to 11 pm. Some larger grocery stores open as early as 6 am, and a few of the hypermarkets in Prague (usually well outside of town along the metro lines) are open 24 hours. Department stores often stay open until 9 or even 10 pm. Outside Prague, most stores close for the weekend at noon on Saturday, although you may find a grocery store open at night or on the weekend.
January 1; Easter Monday; May 1 (Labor Day); May 8 (Liberation Day); July 5 (Sts. Cyril and Methodius Day); July 6 (Jan Hus Day); September 28 (Day of Czech Statehood); October 28 (Czech National Day); November 17 (Day of a Struggle for Liberty and Democracy, aka "Velvet Revolution" Day); and December 24, 25, and 26 (Christmas Eve, Christmas Day, Boxing Day).