What are trim tabs on a boat? Trim tabs ensure that your boat will run level in all sea and weather conditions. They also help ships board a plane faster, fix visibility issues, and make the overall boating experience safer.

The boat’s trim tabs operate directly from the dashboard. Please keep reading to learn how to use trim tabs, their benefits, and the navigation problems they can solve.

How Trim Tabs Work

Attached to the stern of the boat, they can be adjusted to tilt it, port or starboard, using hydraulic or mechanical actuators or jacks. The position of the trim tabs, which is at the rear, is key to how they perform their function. They are either mounted in pockets (assuming your boat has them) on the transom or flush mounted on the same.

The two legs are positioned on either side of the stern to easily correct heeling or inclination. For example, with standard Lemco electric trim tabs, you will receive a controller for either tab on the dash with lights indicating how far you have deployed each.

In this case, “deploying” is simply lowering the trim tabs plate to the point that they will begin to deflect water, lifting the side of the stern that has been listed to level the boat.

Here are sample browsing scenarios that highlight the importance of tabs

  • Suppose you are dealing with uneven loads or the vessel is tilting to the port side due to stronger waves or winds. If this is the case, you will only have to deploy the tab on the port side until your boat stabilizes. Many boats suffer from this when idling, and trim tabs can almost always correct it instantly.
  • Once you slow down after speeding up, the bow of your ship will tend to rise, which will greatly affect your visibility. If you have marine trim tabs, you only need to lower them both to keep your boat in a plane even when it starts cruising at slower speeds.
  • Other elements cause the arc to rise and fall, and this is called porpoising. You may also need to lower both tabs if this is the case, but you may need to do this in quick bursts until it stops. This way you won’t have to slow down just to make the right adjustments.

Other Sailing Situations When Trim Tabs Shine Brightest

boat flaps

1. When you have too many passengers

I have met many boaters who take many people with them on their boating holidays. Usually this results in a very high bow rise which is difficult to correct unless you have trim tabs which not only balance the boat but also raise the stern so you can come in flat faster.

This way you don’t always have to ask people to move forward or use the correct carrier for the usual number of passengers you are carrying with you. Of course, there’s no reason why you should refrain from doing either of these two. The fact is that trim tabs can serve both purposes if used correctly.

2. When you have too much water sprayed on each side of the boat

Almost any savvy sailor will say that you can’t get too much water sprayed over the side of the boat, especially when cruising in rougher waters. Usually these sprays occur on the side of the boat that is elevated. With tabs, you can knock them out earlier by lowering that side.

The decision to lower or raise should be dictated by the design of your boat. If it’s a soft-chine boat, it may actually be best to raise the side so that the spray only ends up above you and a little further aft.

The great thing about most trim tab setups is that you have a lot of freedom to experiment a bit and try out what works best for your particular vessel. Even so, for all their benefits, boat trim tabs are actually optional.

That being said, sailors who regularly sail or fish usually can’t live without these handy gears because of how they can help overcome common obstacles like the ones we’ve mentioned here.

A word of caution when using trim tabs on your boat


Suffice it to say that there are many good things to be said when it comes to the question, what do trim tabs do on a boat? However, the phrase “too much of a good thing” may actually ring true in this case.

  • Excessive adjustment at high speeds can cause boats to suddenly swerve in a different direction, increasing the risk of accidents.
  • Trim tabs are not immune to corrosion buildup. This can affect their performance, to the point that they may not work when you need to use them. For great maintenance tips, please take the time to watch the following video:

Overall, you should be prepared to proactively adjust the trim tabs based on the list that occurs. This is especially true if you have overextended a tab and the water and wind conditions have since changed.


1. Do trim tabs slow a boat down?

The trim tabs cause some drag when deployed. However, they are only really necessary if the waves and the wind are choppy. Most of the time this is the case in oceans but not in rivers and lakes, so if you don’t want to deal with speed reduction, it’s best to stick with the latter.

2. Are trim tabs worth it?

If you find yourself facing the challenges we have mentioned here, then yes, they are worth adding to your boat. To me they are a must have for anyone who enjoys boating, fishing or boating on a regular basis as they reduce engine load saving you more money in the long run.


We hope we have answered your question, “What are trim tabs on a boat?” with the entries we have provided here. All in all, upgrading a boat becomes a piece of cake with these gadgets. They are equally useful in a myriad of boating situations. Make sure you know the best situations to use them, realize when you’re using them incorrectly, and maintain them when they’re already showing signs of wear.