Currency: U.S. dollar. Bills under $20 are universally accepted. $20 bills can be frowned upon for smaller transactions. $50 and $100 bills seem to be frowned upon no matter what the transaction; getting change seems to be a major inconvenience. Carrying plenty of smaller bills is suggested. 

ATM machines in all 78 municipalities of Puerto Rico

Branch opening Sundays: Banco Popular at Plaza las Americas in Hato Rey

Western Union: Tourist zone served at Pueblo at Calle de Diego in Condado, Pueblo at  Avenida los Gobernadores in Isla Verde and Pueblo at Plaza de Armas in Viejo San Juan (Old San Juan)

MoneyGram: Tourist zone served at Grande in Avenida Isla Verde in Isla Verde

Puerto Rican banks include:

>Banco Popular - The biggest and most important bank of Puerto Rico.  (Tourist zone branch in Condado: 787-725-4189)

>Western Bank - No longer a separate Puerto Rican bank, was aquired by Popular in 2010.

>Doral - (Tourist zone branch located at Avenida Isla Verde in Isla Verde, close to Grande supermarket)

American Banks operating in Puerto Rico include:

>Citibank (Tourist zone branch in Condado 787-721-6416)

Spanish Banks operating in Puerto Rico include:

>Banco de Santander (Branch Isla Verde -787-982-5300)

>BBVA (Branch Hato Rey - 787-777-2000)

Canadian Banks include:

>Scotiabank (787-758-8989)