Question

The headquarters for both major American political parties are located in Baltimore, MD Philadelphia, PA Washington

d. c. New York City, NY.

Answer 1

If you're talking about Republicans and Democrats than their headquarters is in Washington D.C.

Answer 2

I believe the answer is: Washington DC

Washington DC is a place where most of the government meetings conducted on federal level is being held (along with the president's office) . Because of this, both major political parties in united states are headquartered in this area for the convenience of their members.