Citizens of the USA traveling to Spain for less than 90 days do not need a visa. But they require a passport which is valid for at least six months beyond their stay. Immigration officers may also ask to see enough funds for their stay and a return airline ticket.
Australian citizens visiting Spain or any other country in the Schengen area (Austria, Belgium, Czech Republic, Denmark, Estonia, Finland, Germany, Greece, Hungary, Iceland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, France, Sweden) for less than 90 days do not require a visa. Passports need to have at least six-month validity.
EU, EEA and Swiss Citizens
As citizens of the European Union and European Economic Area, you will not need a visa to enter the country.
EU member countries
Germany, Austria, Belgium, Bulgaria, Cyprus, Croatia, Denmark, Slovakia, Slovenia, Spain, Estonia, Finland, France, Greece, Hungary, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Poland, Portugal, United Kingdom, Czech Republic, Romania and Sweden.
Iceland, Liechtenstein and Norway.
Citizens of the following countries do not need a visa to enter Spain
The following countries do not require a visa for visits of less than 90 days, but require a valid passport to enter Spain.
Andorra, Antigua and Bermuda, Argentina, Bahamas, Barbados, Bolivia, Bosnia, Brunei, Canada, Chile, Costa Rica, El Salvador, Guatemala, Honduras, Hong Kong, Israel, Japan, Korea, Macao, Malaysia, Mauritius, Mexico, Monaco, Montenegro, Nicaragua, New Zealand, Panama, Paraguay, Saint Kitts and Nevis, San Marino, Serbia, Seychelles, Singapour, Taiwan, Uruguay and Venezuela.
For citizens of countries not mentioned, visit your country's Spanish Embassy or check the Spanish Ministry of Foreign Affairs' website for more information.