You can find ATMs of the different local (and some international) banks everywhere across the city. Most ATMs are situated inside malls, banks and on the outside walls of banks. The latter are accessible 24/7. Outside the Megacity, there are still ATMs in every town. If you plan to go to the deepest countryside or smaller village, though, you might not be able to find an ATM for a while.
Banks are regularly open from 9 am to at least 3 pm. Some, like the Bank of the Philippine Islands, operate until 6 pm. Banks outside the Megacity may close earlier. All banks are closed on national and on many special holidays.