You can arrive in Santander via Santander Airport (SDR)

As an alternative, Bilbao Airport (BIO) is 55 minutes time to Santander by bus

International direct flights from/to Santander Airport:

Berlin, Brussels, Budapest, Dublin, Edinburgh, Lisbon, London, Marrakech, Milan, Rome, Warsaw and Venice

National direct flights from/to Santander Airport:

Barcelona, Gran Canaria, Ibiza, Lanzarote, Madrid, Malaga, Menorca, Palma de Mallorca, Sevilla, Tenerife and Valencia

More info: Santander-Seve Ballesteros Airport