Which Side of a Boat Has a Green Light at Night?

which side of a boat has a green light at night

Things can look pretty confusing when you’re bobbing up and down the waves during a cloudy day. And that’s why lights play an important role in the maritime industry. Using light as a way to signal and inform boats of your presence from a distance, boat owners can effectively curb the risk of various kinds of accidents out on the water.

If you’re new to boating, you might still be a little confused about navigational lights and color-coded lights on a boat. For instance, which side of a boat has a green light at night? Well, we’ve got the answer for you with this short guide.

Green Light on a Boat

According to the quizlet on Boat Ed, the starboard side of the boat should display a green light at night or whenever it might be necessary to use one, like during rough weather. For reference, starboard simply means the right side. The reason why they come up with this technical term is to eliminate the discrepancy of perspective. That is, you can skip the ‘my right, or your right?’ confusion.

How to Remember Where the Green Light Is

Again, it’s not always that easy to remember left and right when you’re on a boat especially because they correspond to different terms and colors. So to help you remember, here are some tips:

Count the Letters

One of the most effective ways to remember where the green light goes would be to count the letters. The opposite of starboard, or port has four letters, which is the same as the number of letters in left. That means that since port is left, it should be red and not green, since green goes with right.

Green Means Right

A green light is usually associated with the idea of correctness. When something is right, it’s green! So when you see a green light on a boat, it’s going to be on the boat’s right side.

Understand the Meanings

Back in the day, boats had a steering oar that was located on the boat’s right side since most people were right handed. Thus that side was named star (Old English steor meaning steer) and board (bord meaning boat’s side) was formed. The opposite side, called port, came around since boats were moored opposite the steering oar.

Why is It Important to Know Green and Red Lights On a Boat?

Aside from being mandated by the law, red and green lights on a boat serve a vital purpose when visibility is less than ideal. Knowing which way a neighboring boat is facing will tell you what direction it’s moving in, allowing boaters to avoid collision.

Remember that boats aren’t like cars that respond to changes in steering instantly. Turning your steering wheel now will only cause a change in direction several seconds later, which is why captains need to constantly be on their feet to anticipate when it’s time to move out of the way.

There are lots of different kinds of lights on a boat, and these include:


These are the red and green lights on either side of the boat. Again, red identifies the boat’s left side, while green identifies the right. They have to be visible no matter where a boat is approaching you from, since they’re intended to help others know your position relative to their own vessel.


This is a bright white light that sits at the stern or the rear of your boat. It should be angled at 135° and must be shining at all times if you’re engine is running between sunset and sunrise.

Masthead Light

The masthead light casts light towards the bow of the boat, and its illumination must be visible from the front and the sides of the vessel. In some cases, boat owners use an all-around light that connects the stern and masthead light into one continuous light.

Remember that all of these lights need to be turned on when you’re underway. Once you dock your boat, you can turn off the sidelights since you’re not moving, and boats won’t have to know which is left and right. All you need to turn on by then would be your stern and masthead lights just to keep your boat visible.

Tips for Boating at Night

There are unique dangers to boating at night. According to statistics, the hours between midnight and 2:30 AM are the most fatal when considering boating accidents. So to help make those wee hours a little safer, consider these tips if you ever find the need to turn on your engine under the cover of darkness:

Go Slow

There’s a lot that could go wrong. Going as slow as possible can help you catch any obstacles or potential collisions before they happen.

Stay Alert

Not just you, but the rest of your crew and passengers. If you’re operating a personal watercraft, ask one of your guests to keep their eyes peeled for any potential dangers.


When your visibility is obstructed, you can always trust what you hear. Listen for any sounds that could indicate that there’s danger afoot. Trust your gut and keep your boat still until you determine where the sounds are coming from.

Take a Break

The invitation to sleep at those strange hours can be pretty strong. If you feel a little too sleepy, don’t hesitate to ask someone else to steer while you snooze.

Trust Your Tools

Those instruments don’t fail you in the morning, so why doubt them now? If your chartplotter is telling you something, make sure you trust what it says especially if it hasn’t played tricks on you in the past.

Tread Lightly

It can be tough to remember which side of a boat has a green light at night, but there are a few tricks you can try to make it easier. And while those colored lights might seem a little silly at the start, they serve a serious purpose that has saved thousands of boats from certain danger especially during those darker hours. So remember these important tidbits of information the next time you set sail at night to steer clear of accidents when visibility might not be the best.

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