Charging is a Basic Action.

From the Saga I Rulebook:


A player may choose to have a character move at one of three different movement rates. However, unlike other actions, a character can only move once per Turn, regardless of the number of Action points available. So, a character that declares Run cannot Walk or do Free Movement in the same turn. A character can not move if it is in Hand-to-hand combat; first it must Escape from combat.

Free Movement: Any character can move 2 inches without using any Action points. Free Movement can be used reactively, so the character can intercept a Charge against a friend unit (although not to avoid a charge against itself).

Walk: The first number in the Speed icon on a character’s card is the distance in inches the character moves while walking. When walking, a character can change direction and turn at will, as long as the total distance walked is not greater than the card’s
indicated movement rate.

Run / Charge: When running or charging, a character moves as many inches as the second number in the Speed icon. Unlike walking, a running character must move in a straight line and cannot turn or change direction. The character can be moved through any scenery features, but cannot charge through impassible scenery.