The best price found from United States to Spain is on June 10th, 2016, travelling with Icelandair. See more options, compare prices and book: search flights.
There are direct flights to Spain from most European countries, as well as North America, South America, Africa, the Middle East and Asia. Those coming from Australasia will usually have to make at least one change of flight.
High season in Spain generally means Christmas, New Year, Easter and roughly June to September. It can be worth playing around with dates close to these times – we found, for example, a massive difference on prices for some Spain-bound intercontinental flights on 12 January (peak season) when compared to a few days later. The applicability of seasonal fares varies, of course, depending on the specific destination. You may find reasonably priced flights to Madrid from elsewhere in Europe in August, for example, because it is stinking hot and everyone else has fled to the mountains or the sea. As a general rule, November to March is when airfares to Spain are likely to be at their lowest, and the intervening months can be considered shoulder periods.
All of Spain's airports share the user-friendly website and flight information telephone number of Aena, the national airports authority. To find more information on each airport, choose 'English' and click on the drop-down menu of airports. Each airport's page has details on practical information (including parking and public transport) and a full list of (and links to) airlines using that airport. It also has current flight information.
Madrid's Aeropuerto de Barajas is Spain's busiest (and Europe's fourth- or fifth-busiest) airport. Other major airports include Barcelona's Aeroport del Prat and the airports of Palma de Mallorca, Málaga, Alicante, Girona, Valencia, Ibiza, Seville and Bilbao. There are also airports at Almería, Asturias, Jerez de la Frontera, Murcia, Reus, Santander, Santiago de Compostela and Seville.