It depends on the package you have contracted:
dT Lite – 120 minutes of calls to landlines in Spain and Europe combined*
dT Total – Unlimited calls to landlines in Spain and 300 minutes of calls to landlines in Europe*
dT ADSL – 120 minutes of calls to landlines in Spain and Europe combined*
* European countries include: Austria, Belgium, Cyprus, Denmark, France, Germany, Greece, Hungary, Ireland, Italy, Luxemburg, Netherlands, Norway, Poland, Portugal, Sweden & U.K. Non-geographical numbers are not included.