Defining 'Out of Bounds' in Golf and the Penalty for Hitting a Ball OB

White lines show where out of bounds begins at Royal St. George golf course No. 14 hole
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"Out of bounds" refers to those areas outside the golf course from which play is not allowed, or any area designated as out of bounds by the committee.

Out of bounds will be marked in some way, often by the use of stakes or some barrier (a fence, for example). Items used to designate out of bounds are not considered obstructions, are considered to be fixed, and therefore cannot be removed in order to play a shot.

"Out of bounds" is often abbreviated in writing as "O.B." or "O.O.B.," and "OB" (oh-bee) is often the spoken shorthand (as in, "That shot might be headed OB").

Official Definition of 'Out of Bounds' In the Rules

This is the official definition of "out of bounds" as it appears in the Rules of Golf, written by the USGA and R&A (note: this is from the condensed Player's Edition; the Full Edition includes a slightly expanded text):

All areas outside the boundary edge of the course as defined by the Committee. All areas inside that edge are in bounds.
The boundary edge of the course extends both up above the ground and down below the ground.
The boundary edge should be defined by boundary objects or lines:
*Boundary objects: When defined by stakes or a fence, the boundary edge is defined by the line between the course -side points of the stakes or fence posts at ground level (excluding angled supports), and those stakes or fence posts are out of bounds.
When defined by other objects such as a wall or when the Committee wishes to treat a boundary fence in a different way, the Committee should define the boundary edge.
*Lines: When defined by a painted line on the ground, the boundary edge is the course -side edge of the line, and the line itself is out of bounds.
When a line on the ground defines the boundary edge, stakes may be used to show where the boundary edge is, but they have no other meaning. Boundary stakes or lines should be white.

White Is the Color of Out of Bounds

As stated in the last sentence of the above definition, when a golf course uses stakes or a line painted on the ground to designate the out-of-bounds boundary, those stakes or that line are white.

(Although if some other boundary — a fence, for example — denotes out of bounds, that type of boundary won't necessarily be white. Many times, though, such OB boundaries are either obvious (a fence along the edge of a golf course property, for example) or are mentioned on the scorecard.)

The Penalty for Hitting a Ball Out of Bounds

The penalty for hitting a golf shot out of bounds, and how to proceed after doing it, are covered in the Rules of Golf in Rule 18.2. That rule begins by noting that "Your ball at rest is out of bounds only when all of it is outside the boundary edge of the course." So, for example, if a white line painted on the turf designated the OB boundary, and your golf is at rest on the line, the ball is in bounds. Rule 18.2 includes a diagram to help golfers determine the in-or-out-of-bounds question.

  • It's a stroke-and-distance penalty for hitting the ball out of bounds. That means, if you are playing by the rules, when you hit a ball OB you must add a penalty stroke to your score, then play another ball from the location of your previous stroke. (Rule 18.2b)
  • If you think you just hit a ball out of bounds, you can play a provisional ball from the same place the first one was played. Be sure to announce your intention to hit a provisional to your playing partners. (Rule 18-3)

If you are not playing by the rules — a friendly round with buddies, none of whom take it too seriously or expect strict adherence to the rules — then for the sake of speeding up play you can ignore stroke-and-distance. Just add a penalty stroke and drop a ball at the place your original shot went out of bounds.

Also note that you are allowed to stand out-of-bounds to play a ball that is in bounds.