Collision rules (rules of the road)
Find out about important rules of the road for powerboats and sailboats in Western Australian waters.
Understanding the basics
Western Australia follows internationally established rules of the road for boating.
Following is a brief summary of the most important rules:
- Always keep a lookout for other vessels and be ready to give way.
- When giving way, do so early and make your intentions obvious to other vessels.
- Power boats should keep away from sail boats and any vessel involved in activities that may affect their manoeuvrability, such as fishing, dredging, and cable laying.
Rules regarding approaching vessels

If a vessel approaches:
- To port (left of the boat), maintain your course and speed with caution.
- To starboard (right of the boat), keep out of its way. (This may not apply if one or both vessels are sailboats).
- The stern (behind the board), maintain your course and speed with caution.
The golden rule
Look to the right, give way to the right, turn to the right and stay to the right.
Always keep right in channels.
Rules for powerboats

Head on situation
When 2 powerboats are meeting head on, each vessel must give way to starboard (right) and pass well clear of each other.

When crossing the path of another powerboat, give way to the vessel on the starboard (right) side.

Boats can overtake each other on either side as long as it is safe to do so. However, the overtaking vessel (including sailboats), must keep well clear of the other vessel.
Rules for sailboats

Wind on different sides
When 2 sailing vessels meet, but have the wind on a different side, the vessel with the wind on the port side should give way.
A keeps clear of B
If a sailing vessel with the wind on port side cannot determine whether another sailing vessel has the wind on the port or starboard side, it should keep out of the way.

Wind on the same sides
When 2 sailing vessels meet and both have the wind on the same side, the vessel which is in the flow of the wind (windward) shall keep out of the way of the vessel which is against the wind (leeward).
B keeps clear of A
The windward side is defined as:
- Fore-and-aft rigged vessel; the side opposite to that on which the mainsail is carried.
- Square-rigged vessel; the side opposite to that on which the largest fore-and-aft sail is carried.
When power meets sail
In general, powered vessels should give way to sail.

However, everyone has a responsibility to avoid collisions so, even if the rules require another vessel to keep out of your way, you must be ready to take action yourself to avoid a collision.