Madrid is 6 hours ahead of Boston. When it's 9:00 AM in Boston, it's 3:00 PM in Madrid. Both cities observe DST, maintaining the 6-hour difference year-round.
Boston uses ET (Eastern Time) while Madrid uses CET/CEST.
Optimal window: 8:00 AM - 12:00 PM Boston time (2:00 PM - 6:00 PM Madrid). Morning calls from Boston reach afternoon business hours in Madrid.
Boston has direct flights to Madrid with Iberia, popular for business and cultural exchange.