Most offices, including banks, are open 9 a.m.–5 or 5:30 p.m. on weekdays. Shop hours vary greatly, but with the exception of smaller boutiques or antiques stores, which often have limited hours, most stores are open at least 10 or 11 a.m.–6 or 7 p.m. Monday–Saturday, and are closed or have very limited hours on Sunday. Many downtown shops stay open as late as 9 p.m. on Wednesday evening to accommodate after-work shoppers.
Most restaurants serve food until 9 or 10 p.m. on weeknights and until 10 or 11 p.m. on weekends, with some restaurants in the most active parts of town (like Rittenhouse Square [1], Old City, South Street, Northern Liberties, and Manayunk) offering late-night menus. Many bars serve food until midnight or 1 a.m. and some Chinatown restaurants stay open until 3 a.m. Other than that, late-night dining is generally limited to diners and cheesesteak and pizza joints—some of which are open 24 hours. With the exception of a few private clubs and after-hours clubs, bars in Philadelphia [2] close at 2 a.m. sharp.
Links:
[1] http://www.moon.com/destinations/philadelphia/arts-and-leisure/recreation/parks-and-gardens/rittenhouse-square
[2] http://www.moon.com/destinations/philadelphia/discover-philadelphia