Are you ready to hit the water and enjoy some boating at night? There’s something magical about being out on the water under a starry sky, but it’s important to remember that boating in low visibility conditions can be dangerous if not done properly.
That’s why I wrote this article about boat navigation light rules, which reflects on my own experience fishing early morning or staying out until dusk. These rules are important because they keep us safe in low visibility conditions, and they work together with right-of-way rules to help us avoid accidents.
In this article, we’ll explore the basics of navigation light rules for boats, including what types of lights are needed and when, as well as basic rules for different types of boats.
But don’t worry, I’ll explain everything in a simple way so you can navigate with confidence and avoid any hazards.
So let’s get started!
Table of Contents
Key night navigation safety points
Navigating a boat in the dark can be challenging and risky, and it’s essential to take some extra precautions to ensure your safety and the safety of others on the water. Here are some key night navigation safety points that you should keep in mind:
Slow down
At night, it can be challenging to spot hazards in the water. To give yourself more time to react and avoid accidents, it’s essential you take it easy and slow down. Reducing the boat’s speed can make a significant difference in avoiding a collision with other boats and objects in the water.
Be seen
Visibility is crucial when navigating at night. While you might be able to see other boats, they might not be able to see you, so it’s essential to have proper navigation lights and other signaling devices in good working condition. These lights help other boaters know where you are and the direction you’re traveling in.
Keep a lookout
Keep a constant lookout for other boats and obstacles such as rocks, shoals, and buoys when navigating at night. Listen out for other boats’ engines as well to get a sense of their proximity.
Know your waterway
Make sure you’re familiar with the waterway you’re navigating and the location of navigation aids that highlight hazards. It’s important to be familiar with local navigation charts, and use that knowledge when navigating at night. Know the depth of the water and avoid areas that may be hazardous, such as shallow areas or areas with underwater obstructions.
Never assume
Don’t assume that other boaters have seen you or know the navigational rules. Stay alert and be ready to maneuver to avoid collisions. It’s always better to err on the side of caution and take evasive action when in doubt.
Following these simple but crucial safety points can help you navigate safely at night and reduce the risk of accidents. Remember, safety should always be your top priority when on the water, especially at night when visibility is limited.
Boat light types
There are four main types of lights that boaters use for navigation purposes:

Masthead lights
Masthead lights are placed on the top of the boat’s mast and shine white light forward and to the sides of the boat. They form a 225 degrees visibility arc from the centerline, including 112.5 degrees to port (left) and 112.5 degrees to starboard (right).
All-round lights
All-round lights are mounted on a pole typically at the center of the boat, or on the mast, and shine white light in all directions (360 degrees).
Sidelights
Sidelights are mounted on the sides of the boat, with the red light on the port (left) side and the green light on the starboard (right) side. Each of them forms a 112.5 degrees arc from dead ahead (forward) to 22.5 abaft (rear).
Sternlights
Sternlights are mounted on the back of the boat and shine white light aft (behind) the boat. They are visible from 135 degrees, which means that they can be seen from behind the boat.
Now that you know about the different types of boat lights, it’s time to dive into the basic marine navigation lights rules. These rules dictate when and where each type of light should be used, and are essential for safe navigation on the water. Let’s explore them in detail.
What are the boat navigation light rules?
Boat light rules are defined by the USCG (United States Coast Guard) to ensure safe navigation on the water, especially at night or during periods of reduced visibility.
These rules exist to prevent collisions between boats and to help boaters determine the direction and status of other vessels.
It’s important to note that state governments may have additional requirements on top of the USCG regulations, so it’s essential to know the local regulations before heading out on the water.
In general, boaters are required to display the appropriate navigation lights between sunset and sunrise or during periods of reduced visibility. The USCG Navigation Light Rules dictate the type, position, and color of the lights that should be displayed on a boat, depending on the size and type of the vessel.
Here are some of the basic boat lights rules that apply to recreational boats when underway:
- Boats under 23 feet (7 meters) and a maximum speed capacity of 7 knots – Powerboats and sailboats can use all-round white light, and if practicable may display sidelights as well.
- Boats under power up to 39 feet (12 meters) – Must display an all-round white light visible for at least 2 nautical miles, and sidelights (red/green) visible for at least 1 nautical mile. Or they may replace the all-round light with a masthead light (white) plus sternlight (white) also visible for at least 2 nautical miles.
- Boats under sail up to 39 feet (12 meters) – Must display sidelights (red/green) visible for at least 1 nautical mile, and a sternlight (white) visible for at least 2 nautical miles. These lights may be combined in a tri-color light near the top of the mast.
- Boats under power, between 39 and 65 feet (12 to 20 meters) – Must display a masthead light, sternlight, and sidelights as described above. But the masthead light must be visible for at least 3 nautical miles and the stern and sidelights visible for 2 nautical miles.
- Boats under sail between 39 and 65 feet (12 to 20 meters) – Must display sidelights and sternlight, or a tri-color light as described above. But these must be visible for at least 2 nautical miles.
- All boats over 65 feet (20 meters) – Must have the lights described above, with masthead lights visible for at least 6 nautical miles and the other for at least 3 nautical miles. Also, larger boats over 164 feet (50 meters) must display a second masthead light abaft, higher than the forward one.
In addition to these, there are also some anchor light rules all boats need to follow.
- Boats up to 164 feet (50 meters) at anchor – must display an all-round white light where it is most visible.
It is important to note that sailboats under power are considered powerboats, and must abide by the same navigation light rules as other boats under power.
Remember these are just the basic rules for boat lights, other boat types may have additional requirements. So it’s important to consult the USCG Navigation Light Rules and your local boating authorities for more specific cases and any updates.
In the next section, we’ll cover a helpful navigation lights checklist to make sure you have everything you need to stay safe on the water.
Navigation lights checklist

Here is a checklist that you can use to ensure your safety and the safety of others when navigating at night. By following these simple steps, you can be confident that your boat’s lights are working correctly, and that you are taking all the necessary precautions to avoid any accidents while on the water.
- Familiarize yourself with the lighting requirements for your boat type and size.
- Clean and maintain your navigation lights regularly to ensure maximum visibility.
- Check that your navigation lights are functioning correctly, and carry extra bulbs as a backup.
- Proceed with caution and reduce speed when navigating at night.
- Stay alert and keep an eye out for anything that could obstruct your path.
- Try to travel with someone else, extra eyes on board can help with navigation.
- If visibility is severely restricted do not continue, use sound signals to alert other boaters.
- Use an all-round white light whenever your vessel is at anchor.
Now it’s time to put your knowledge into practice. In the next section, I’ll cover how to interpret the lights you see on the water and provide scenarios for various light configurations. This will give you the confidence to navigate through different situations safely and efficiently.
Interpreting what you see when on the water
Interpreting what you see when on the water correctly is a matter of safety, especially at night or in times of limited visibility. Understanding the navigation light combinations of other boats can help you determine their direction, whether they are coming towards you or moving away.
As a power-driven vessel, you should know how to interpret some common scenarios:
If you see a green and a white light

This is possibly another power-driven boat, you are seeing her starboard and are in crossing paths. This means you are the stand-on vessel.
Remain alert in case the other vessel has not seen you or doesn’t know the nav light rules.
If you only see a white light

It could be another boat’s stern or an anchored boat. In any case, the other boat is the stand-on vessel, and you may go around on either side at a safe distance and speed.
If you see a red and a white light

This is possibly another power-driven boat you are seeing on her port side and are in crossing paths. This means you are the give-way vessel.
Slow down or turn to starboard (right) and pass behind the other boat. Remain alert in case the other vessel has not seen you or they don’t know the navigational rules.
If you see a green, a red and a white light

You are likely approaching another power-driven boat head-on and both of you must give way by turning to starboard (right) and maintaining a safe distance and speed.
If you see a green, and a red light without white light

You are likely approaching a sailboat (under sail) head-on.
Since you are a power-driven boat, the boating right-of-way rules indicate you must give way and maintain a safe distance and speed.
If you only see a green light or only a red light

You are likely approaching a sailboat (under sail) and you must give way.
Remember a sailboat under sail has right of way except when overtaking.
Final words
Navigating at night can be challenging, but with proper preparation and knowledge, you can ensure the safety of yourself and others on the water.
Remember to slow down, be seen, keep a lookout, know your waterway, and never assume. Familiarize yourself with the basic light rules for boats, and always double-check your navigation lights before heading out.
Check out this Boating Right of Way guide and other boat safety articles to make sure that you’re ready to make this upcoming boating season your best one yet. Safe boating!