Presidential Order of Succession 

Under the 25th Amendment of the Constitution of the United States of America (1967), in the event that the President of the United States, for any reason, is unable to continue the Presidential duties, this is the order that is followed to determine whom will succeed to the Presidency. The most immediate official on the list will always be the next in line (unless that official, as well, is unable to continue his or her duties). An official, though his or her office may be part of the succession, will be passed over for the succession if he or she does not meet all of the requirements set forth by the United States Constitution. This list is also known as the Order of Presidential Succession. The order is:

Vice President of the United States
Speaker of the House of Representatives
President Pro-Tempore of the United States Senate
Secretary of State
Secretary of the Treasury
Secretary of Defense
Attorney General
Secretary of the Interior
Secretary of Agriculture
Secretary of Commerce
Secretary of Labor
Secretary of Health and Human Services
Secretary of Housing and Urban Development
Secretary of Transportation
Secretary of Energy
Secretary of Education
Secretary of Veteran's Affairs
Secretary of Homeland Security

The Presidential Order of Succession has never been utilized beyond the point of Vice President.

Presidential Order of Succession by Nicolai August 11, 2004